Pyrrolo [4,3,2-de] quinoline derivatives

ABSTRACT

LK6-A derivatives which have immmunosuppressive activity, cell growth inhibitory activity, anti-tumor activity, etc. and which are represented by general formula (I):as defined herein, and pharmaceutically acceptable salts thereof.

This application is a 371 of PCT/JP99/03691, filed on Jul. 8, 1999.

TECHNICAL FIELD

The present invention relates to LK6-A derivatives which have immmunosuppressive activity, cell growth inhibitory activity, anti-tumor activity, etc., and pharmaceutically acceptable salts thereof.

BACKGROUND ART

Cyclosporin A [Nature, Vol. 280, p. 148 (1978)], FK506 [Immunol. Today, Vol. 10, p. 6 (1989)], mizoribine [Transplantation Proceed., Vol. 11, p. 865, (1979)], azathioprine [New Eng. J. Med., Vol. 268, p. 1315 (1963)], 15-deoxyspergualin [Transplantation Proceed., Vol. 22, p. 1606 (1990)], etc., which are known as low-molecular immunosuppressive agents, are used as therapeutic agents for autoimmune diseases, allergic diseases, infections caused by organ transplantation, etc. or as rejection inhibitors in organ transplantation. However, they are not entirely satisfactory in respect of efficacy, side effect, etc.

Plakinidines [Tetrahedron Lett., Vol. 31, p. 3271 (1990)] are reported as compounds having the pyrrolo[4, 3, 2-de]quinoline skeleton, but their immunosuppressive activity has not been known. As the pyrrolo[4, 3, 2-de]quinoline compound having immunosuppressive activity, LK6-A represented by the following formula (Japanese Published Unexamined Patent Application No. 151185/97) has been reported.

DISCLOSURE OF THE INVENTION

An object of the present invention is to provide novel LK6-A derivatives having excellent immunosuppressive activity, cell growth inhibitory activity, anti-tumor activity, etc. which are useful as therapeutic agents for autoimmune diseases, allergic diseases, and diseases caused by abnormal cell growth such as leukemia and cancers, or as rejection inhibitors in organ transplantation.

The present invention relates to LK6-A derivatives represented by general formula (I):

[wherein R¹ represents lower alkyl (the lower alkyl may be substituted by one to a substitutable number of, preferably 1-4 substituents which are the same or different and are selected from the group consisting of lower alkyl, hydroxy, lower alkoxy and halogen), lower alkanoyl (the lower alkyl moiety of the lower alkanoyl may be substituted by one to a substitutable number of, preferably 1-4 substituents which are the same or different and are selected from the group consisting of lower alkyl, hydroxy, lower alkoxy and halogen), carboxy, lower alkoxycarbonyl,

(wherein n represents 1 or 2) or COCH═CHR⁹ {wherein R⁹ represents substituted or unsubstituted lower alkoxy, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl or NR¹⁰R¹¹ (wherein R¹⁰ and R¹¹, which may be the same or different, each represents hydrogen, substituted or unsubstituted lower alkyl, substituted or unsubstituted lower alkenyl, substituted or unsubstituted lower alkynyl, substituted or unsubstituted aralkyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted heteroaryl-substituted lower alkyl, substituted or unsubstituted tetrahydropyranyl, or substituted or unsubstituted tetrahydropyranylmethyl, or R¹⁰ and R¹¹ are combined together with the adjoining N to form a substituted or unsubstituted heterocyclic group)};

R² represents hydrogen, substituted or unsubstituted lower alkyl, substituted or unsubstituted lower alkenyl, substituted or unsubstituted lower alkynyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted lower alkanoyl, substituted or unsubstituted lower alkanoyloxy; halogen, SR¹² (wherein R¹² represents substituted or unsubstituted lower alkyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted aralkyl, substituted or unsubstituted heteroaryl-substituted lower alkyl, substituted or unsubstituted tetrahydropyranyl, or substituted or unsubstituted tetrahydropyranylmethyl), NR¹³R¹⁴ (wherein R¹³ and R¹⁴ have the same significances as the above R¹⁰ and R¹¹, respectively) or azido;

R²′ represents hydrogen or is combined with R³ to represent a bond;

R³ represents substituted or unsubstituted lower alkanoyl or is combined with R²′ to represent a bond;

R⁴ and R⁵, which may be the same or different, each represents hydrogen, substituted or unsubstituted lower alkyl, substituted or unsubstituted lower alkanoyl, substituted or unsubstituted lower alkoxycarbonyl, substituted or unsubstituted aralkyloxycarbonyl, or substituted or unsubstituted heteroaryl-substituted lower alkoxycarbonyl;

R⁶ represents hydrogen or halogen; and

R⁷ and R⁸, which may be the same or different, each represents hydrogen, substituted or unsubstituted lower alkyl, or substituted or unsubstituted lower alkanoyl;

provided that a compound wherein R¹ represents (E)-3-methoxyacryloyl, R², R⁴, R⁵ and R⁶ represent hydrogen, R²′ and R³ are combined together to represent a bond, R⁷ represents hydrogen and R⁸ is acetyl is excluded], and pharmaceutically acceptable salts thereof.

Hereinafter, the compounds represented by general formula (I) are referred to as Compounds (I). The same shall apply to compounds of other formula numbers.

Preferred examples of the compounds of the present invention are shown in the following (a)-(h).

(a) Compound (I) in which R¹ represents COCH═CHR⁹ (wherein R⁹ has the same significance as defined above); R²′ and R³ are combined together to represent a bond; R⁴, R⁵ and R⁶ represent hydrogen; and R⁷ and R⁸, which may be the same or different, each represents hydrogen or acetyl.

(b) Compound (I) in which R¹ represents lower alkyl (the lower alkyl may be substituted by one to a substitutable number of, preferably 1-4 substituents which are the same or different and are selected from the group consisting of lower alkyl, hydroxy, lower alkoxy and halogen) or lower alkanoyl (the lower alkyl moiety of the lower alkanoyl may be substituted by one to a substitutable number of, preferably 1-4 substituents which are the same or different and are selected from the group consisting of lower alkyl, hydroxy, lower alkoxy and halogen); R²′ and R³ are combined together to represent a bond; R⁴, R⁵ and R⁶ represent hydrogen; and R⁷ and R⁸, which may be the same or different, each represents hydrogen or acetyl.

(c) Compound (I) in which R¹ represents:

(wherein n has the same significance as defined above); R²′ and R³ are combined together to represent a bond; R², R⁴, R⁵ and R⁶ represent hydrogen; and R⁷ and R⁸, which may be the same or different, each represents hydrogen or acetyl.

(d) Compound (I) in which R¹ represents (E)-3-methoxyacryloyl; R²′ and R³ are combined together to represent a bond; R⁴ represents hydrogen; and R⁵ represents substituted or unsubstituted lower alkoxycarbonyl or substituted or unsubstituted aralkyloxycarbonyl.

(e) Compound (I) in which R¹ represents COCHR¹⁵CH(OCH₃)₂ (wherein R¹⁵ represents hydrogen or lower alkyl); R²′ and R³ are combined together to represent a bond; R⁴ and R⁵, which may be the same or different, each represents hydrogen or lower alkyl; and R⁷ and R⁸, which may be the same or different, each represents hydrogen, substituted or unsubstituted lower alkyl or acetyl.

(f) Compound (I) in which R¹ represents COCHR^(15a)CH(OCH₃)₂ (wherein R^(15a) represents hydrogen or halogen); R²′ and R³ are combined together to represent a bond; R⁴ and R⁵ represent hydrogen; and R⁷, and R⁸, which may be the same or different, each represents hydrogen or acetyl.

(g) Compound (I) in which R¹ represents 1-hydroxy-3-methoxypropyl; R²′ and R³ are combined together to represent a bond; R⁴ and R⁵ represent hydrogen; and R⁷ and R⁸, which may be the same or different, each represents hydrogen or acetyl.

(h) Compound (I) in which R² represents hydrogen or substituted or unsubstituted lower alkanoyloxy; R²′ represents hydrogen; R³ represents substituted or unsubstituted lower alkanoyl; R⁴ represents hydrogen; R⁵ represents substituted or unsubstituted lower alkanoyl; R⁷ represents hydrogen; and R⁸ represents acetyl.

Pharmaceutically acceptable salts of Compounds (I) shown in the above (a)-(h) are also one of the preferred embodiments of the present invention.

In the definitions of the groups in Compounds (I), the halogen means a fluorine, chlorine, bromine or iodine atom.

The lower alkyl includes straight-chain or branched alkyl groups having 1-9 carbon atoms, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, pentyl, hexyl, heptyl, octyl and nonyl.

The lower alkyl moiety of the lower alkanoyl, the lower alkoxy, the lower alkoxycarbonyl and the lower alkanoyloxy has the same significance as the above lower alkyl, and the lower alkyl moiety of the heteroaryl-substituted lower alkyl and the heteroaryl-substituted lower alkoxycarbonyl represents a group in which one hydrogen atom is removed from the above lower alkyl.

The lower alkenyl includes alkenyl groups having 2-6 carbon atoms, such as vinyl, 1-propenyl, butenyl, pentenyl and hexenyl, and the lower alkynyl includes alkynyl groups having 2-6 carbon atoms, such as ethynyl, propynyl, butynyl, pentynyl and hexynyl.

The aryl includes aryl groups having 6-14 carbon atoms, such as phenyl, naphthyl and anthryl, and the heteroaryl includes 5- or 6-membered heteroaryl groups, such as pyridyl, furyl, thienyl, pyrrolyl, imidazolyl, pyrimidinyl, oxazolyl, thiazolyl, bicyclic heteroaryl group such as indolyl, benzofuryl, benzothienyl, quinolyl, quinazolinyl and quinoxalinyl. The heteroaryl moiety of the heteroaryl-substituted lower alkyl and the heteroaryl-substituted lower alkoxycarbonyl has the same significance as the above heteroaryl. The aryl moiety of the aralkyl and the aralkyloxycarbonyl has the same significance as the above aryl. The alkylene moiety of the aralkyl and the aralkyloxycarbonyl represents a group in which one hydrogen atom is removed from the above lower alkyl.

The heterocyclic group formed with the adjoining N includes pyrrolidinyl, piperidino, piperazinyl, morpholino, thiomorpholino, pyrrolyl, imidazolyl and pyrazolyl.

The substituted lower alkyl, the substituted lower alkoxy, the substituted lower alkenyl, the substituted lower alkynyl, the substituted lower alkanoyl, the substituted lower alkanoyloxy, the substituted lower alkoxycarbonyl, the substituted aralkyloxycarbonyl, the substituted aralkyl, the substituted heteroaryl-substituted-lower alkyl and the substituted heteroaryl-substituted lower alkoxycarbonyl each has one to a substitutable number of, preferably 1-5 substituents which are the same or different. Examples of the substituents include NR¹⁶R¹⁷ (wherein R¹⁶ and R¹⁷, which may be the same or different, each represents hydrogen or lower alkyl, or R¹⁶ and R¹⁷ are combined together with the adjoining N to form a heterocyclic group), hydroxy, lower alkoxy and lower alkanoyloxy. The lower alkyl, the heterocyclic group formed with the adjoining N, the lower alkoxy and the lower alkanoyloxy have the same significances as defined above, respectively.

The substituted aryl and the substituted heteroaryl each has 1-3 substituents which are the same or different. Examples of the substituents include lower alkyl, NR^(16a)R^(17a) (wherein R^(16a) and R^(17a) have the same significances as the above R¹⁶ and R¹⁷, respectively), hydroxy, halogen, lower alkoxy, lower alkoxy-substituted lower alkoxy and lower alkanoyloxy. The lower alkyl, the lower alkoxy, the lower alkanoyloxy and the halogen have the same significances as defined above, respectively. The former lower alkoxy of the lower alkoxy-substituted lower alkoxy has the same significance as the above lower alkoxy, and the alkylene moiety of the latter lower alkoxy represents a group in which one hydrogen atom is removed from the above lower alkyl.

The substituted heterocyclic group formed with the adjoining N has 1-3 substituents which are the same or different. Examples of the substituents include hydroxy, lower alkyl, lower alkanoyl and arylcarbonyl. The lower alkyl and the lower alkanoyl have the same significances as defined above, respectively. The aryl moiety of the arylcarbonyl may be substituted by 1-3 functional groups arbitrarily selected from the group consisting of lower alkyl, lower alkanoyl, lower alkanoyloxy, hydroxy, lower alkoxy, amino, nitro, azido, carboxyl and lower alkoxycarbonyl. The alkyl moiety of the lower alkyl, lower alkanoyl, the lower alkanoyloxy, the lower alkoxy and the lower alkoxycarbonyl has the same significance as the above lower alkyl.

The substituted tetrahydropyranyl and the substituted tetrahydropyranylmethyl each has 1-4 substituents which are the same or different. Examples of the substituents include hydroxy, hydroxymethyl, lower alkoxy, lower alkoxymethyl, lower alkanoyloxy, lower alkanoyloxymethyl, benzyloxy, benzyloxymethyl and NR¹⁸R¹⁹ (wherein R¹⁸ and R¹⁹, which may be the same or different, each represents hydrogen, lower alkanoyl, lower alkoxycarbonyl, arylcarbonyl or aralkyloxycarbonyl). The lower alkyl moiety of the lower alkoxy, the lower alkoxymethyl, the lower alkanoyloxy, the lower alkanoyloxymethyl, the lower alkanoyl and the lower alkoxycarbonyl has the same significance as the above lower alkyl. The alkylene moiety of the aralkyloxycarbonyl has the same significance as the above alkylene moiety, and the aryl moiety of the arylcarbonyl and the aralkyloxycarbonyl has the same significance as the above aryl.

The pharmaceutically acceptable salts of Compounds (I) include acid addition salts, metal salts, ammonium salts, organic amine addition salts and amino acid addition salts. Examples of the acid addition salts are inorganic acid addition salts such as hydrochloride, hydrobromide, sulfate and phosphate, and organic acid addition salts such as formate, acetate, oxalate, benzoate, methanesulfonate, p-toluenesulfonate, maleate, malonate, fumarate, tartrate, citrate, succinate and lactate. Examples of the metal salts are alkali metal salts such as lithium salt, sodium salt and potassium salt, alkaline earth metal salts such as magnesium salt and calcium salt, aluminum salt and zinc salt. Examples of the ammonium salts are ammonium salt and tetramethylammonium salt. Examples of the organic amine addition salts are salts with morpholine and piperidine. Examples of the amino acid addition salts are salts with glycine, phenylalanine, aspartic acid, glutamic acid and lysine.

There may be various stereoisomers, regio isomers, geometrical isomers, tautomers, etc. for some of Compounds (I) of the present invention. The present invention encompasses all possible isomers and mixtures thereof in arbitrary mixture ratios.

The processes for preparing Compounds (I) are described below.

In the following processes, if the defined groups change under the conditions of the working method or are not appropriate for carrying out the method, the desired compounds can be obtained by using methods for introducing and eliminating protective groups which are conventionally used in synthetic organic chemistry [e.g., T. W. Greene, Protective Groups in Organic Synthesis, John Wiley & Sons Inc. (1981)]. If necessary, the order of the reaction steps such as introduction of a substituent may be changed.

Process 1

Compound (Ia), i.e., Compound (I) wherein R¹ represents acetyl; R², R⁴, R⁵, R⁶, R⁷ and R⁸ represent hydrogen; and R²′ and R³ are combined together to represent a bond can be prepared according to the following reaction step.

Step 1

Compound (Ia) can be obtained by treating LK6-A with an aqueous alkali solution in a solvent. Suitable solvents are water-miscible ones, for example, lower alcohols such as methanol and ethanol, tetrahydrofuran and dioxane, which may be used alone or as a mixture. As the aqueous alkali solution, 1-10 N aqueous solutions of alkalis such as sodium hydroxide and potassium hydroxide can be used. The reaction is carried out at a temperature between room temperature and the boiling point of the solvent used, preferably 50-100° C. for 0.5-10 hours.

The processes for preparing Compound (II), i.e., Compound (I) wherein R¹ represents COCH═CHR⁹ (wherein R⁹ has the same significance as defined above); R²′ and R³ are combined together to represent a bond; and R⁴, R⁵ and R⁶ represent hydrogen are described in the following processes 2-7.

Process 2

Compound (IIa), i.e., Compound (I) wherein R², R⁴, R⁵ and R⁶ represent hydrogen; R²′ and R³ are combined together to represent a bond; R¹ represents COCH═CHNR¹⁰R¹¹ (wherein R¹⁰ and R11 have the same significances as defined above); R⁷ represents hydrogen; and R⁸ represents acetyl can be prepared according to the following reactions step.

(In the formula, R¹⁰ and R¹¹ have the same significances as defined above.)

Step 2

Compound (IIa) can be obtained by reaction of LK6-A with 1-20 equivalents of HNR¹⁰R¹¹ (wherein R¹⁰ and R¹¹ have the same significances as defined above) in an inert solvent. As the inert solvent, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, tetrahydrofuran, etc. may be used. The reaction is carried out at 0-100° C., preferably 20-50° C. for 0.5-12 hours.

Process 3

Compound (IIb), i.e., Compound (I) wherein R¹ represents COCH═CHNR¹⁰R¹¹ (wherein R¹⁰ and R¹¹ have the same significances as defined above), R² represents NR¹³R¹⁴ (wherein R¹³ and R¹⁴ have the same significances as defined above, but NR¹³R¹⁴ here is the same as the above NR¹⁰R¹¹); R⁴, R⁵ and R⁶ represent hydrogen; R²′ and R³ are combined together to represent a bond; R⁷ represents hydrogen; and R⁸ represents acetyl can be prepared according to the following reaction step.

(In the formula, R¹⁰, R¹¹, R¹³ and R¹⁴ have the same significances as defined above, and NR¹³R¹⁴ is the same as NR¹⁰R¹¹.)

Step 3

Compound (IIb) can be obtained by reaction of LK6-A with 2-100 equivalents of HNR¹⁰R¹¹ (wherein R¹⁰ and R¹¹ have the same significances as defined above) under the conditions similar to those in step 2.

Process 4

Compound (IIc), i.e., Compound (I) wherein R¹ represents (E)-3-methoxyacryloyl; R² represents SR¹² (wherein R¹² has the same significance as defined above); R²′ and R³ are combined together to represent a bond; R⁴, R⁵ and R⁶ represent hydrogen; R⁷ represents hydrogen; and R⁸ represents acetyl can be prepared according to the following reaction step.

(In the formula, R¹² has the same significance as defined above.)

Step 4

Compound (IIc) can be obtained by reaction of LK6-A with 1-20 equivalents of HSR¹² (wherein R¹² has the same significance as defined above) in an inert solvent. The solvent, reaction temperature and reaction time are substantially the same as in the above step 2.

Process 5

Compound (IId), i.e., Compound (I) wherein R¹ represents (E)-3-methoxyacryloyl; R² represents halogen; R²′ and R³ are combined together to represent a bond; R⁴, R⁵ and R⁶ represent hydrogen; R⁷ represents hydrogen; and R⁸ represents acetyl can be prepared according to the following reaction step.

(In the formula, X¹ represents halogen.)

The halogen represented by X¹ has the same significance as the above halogen.

Step 5

Compound (IId) can be obtained by reaction of LK6-A with 1-20 equivalents of a halogenating reagent in an inert solvent.

As the inert solvent, halogen solvents such as dichloromethane, chloroform and carbon tetrachloride, ethers such as tetrahydrofuran and dioxane, lower alcohols such as methanol and ethanol, ethyl acetate, dimethylformamide, etc. may be used alone or as a mixture.

Examples of the halogenating reagent include bromine, chlorine, iodine, N-chlorosuccinimide, N-bromosuccinimide, N-iodosuccinimide, tetrabutylammonium tribromide and pyrrolidone hydrotribromide. The reaction is carried out at a temperature between −20° C. and the boiling point of the solvent used, preferably between 0° C. and room temperature for 0.1-12 hours.

Process 6

Compound (IIe), i.e., Compound (I) wherein R¹ represents (E)-3-methoxyacryloyl; R² represents hydrogen, halogen, SR¹² (wherein R¹² has the same significance as defined above) or NR¹³R¹⁴ (wherein R¹³ and R¹⁴ have the same significances as defined above); R²′ and R³ are combined together to represent a bond; R⁴, R⁵ and R⁶ represent hydrogen; R⁷ represents hydrogen; and R⁸ represents acetyl can be prepared according to the following reaction step.

{In the formula, R^(2a) represents hydrogen, halogen, SR¹² (wherein R¹² has the same significance as defined above) or NR¹³R¹⁴ (wherein R¹³ and R¹⁴ have the same significances as defined above).}

The halogen represented by R^(2a) has the same significance as the above halogen.

Step 6

Compound (IIe) can be obtained by heating Compound (IIIa) or (IIIb) obtained in the following process 8 or 9 in an inert solvent, if necessary, in the presence of molecular sieves. As the inert solvent, dimethyl sulfoxide, dimethylformamide, etc. may be used. The reaction is carried out at a temperature between 50° C. and the boiling point of the solvent used, preferably 90-100° C. for 1-120 hours.

Process 7

Compound (IIf), i.e., Compound (I) wherein R¹ represents (E)-COCH═CHAr (wherein Ar represents substituted or unsubstituted aryl or substituted or unsubstituted heteroaryl which has the same significance as defined above); R², R⁴, R⁵, R⁶, R⁷ and R⁸ represent hydrogen; and R²′ and R³ are combined together to represent a bond can be prepared according to the following reaction step.

(In the formula, Ar represents substituted or unsubstituted aryl or substituted or unsubstituted heteroaryl which has the same significance as defined above.)

Step 7

Compound (IIf) can be obtained by reaction of Compound (Ia) obtained in process 1 with 1-20 equivalents of an aldehyde represented by ArCHO (wherein Ar has the same significance as defined above) in an inert solvent in the presence of a base.

As the inert solvent, lower alcohols such as methanol and ethanol, ethers such as ether, tetrahydrofuran and dioxane, dimethylformamide, water, etc. may be used alone or as a mixture. As the base, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium hydride, potassium tert-butoxide, 1,4-diazabicyclo[2.2.2]octane, 1,8-diazabicyclo[5.4.0]undec-7-ene, etc. may be used in an amount of 0.1-6 equivalents based on Compound (Ia). The reaction is carried out at a temperature between 0° C. and the boiling point of the solvent used, preferably between 0° C. and room temperature for 1-240 hours.

The processes for preparing Compound (III), i.e., Compound (I) wherein R¹ represents CR¹⁸R¹⁹CH₂CH(OCH₃)₂ (wherein R¹⁸ represents hydrogen or is combined with R¹⁹ to represent ═O, and R¹⁹ represents hydroxy or is combined with R¹⁸ to represent ═O); R⁴, R⁵ and R⁶ represent hydrogen; and R² and R³ are combined together to represent a bond are described in the following processes 8 and 9.

Process 8

Compound (IIIa), i.e., Compound (III) wherein R¹⁸ and R¹⁹ are combined together to represent ═O; R² represents hydrogen; R⁷ represents hydrogen; and R⁸ represents acetyl can be prepared according to the following reaction step.

Step 8

Compound (IIIa) can be obtained by reaction of LK6-A with 1-100 equivalents of methanol in an inert solvent, if necessary, in the presence of a base. As the inert solvent, halogen solvents such as dichloromethane and chloroform, ethers such as tetrahydrofuran and dioxane, dimethyl sulfoxide, dimethylformamide, etc. may be used. Methanol may be used also as the solvent. As the base, sodium carbonate, potassium carbonate, sodium hydroxide, potassium hydroxide, 1,4-diazabicyclo[2.2.2]octane, 1,8-diazabicyclo[5.4.0]undec-7-ene, triethylamine, diisopropylethylamine, etc. may be used in an amount of 0.1-20 equivalents based on LK6-A. The reaction is carried out at a temperature between 0° C. and the boiling point of the solvent used, preferably 20-60° C. for 1-48 hours.

Process 9

Compound (IIIb), i.e., Compound (III) wherein R¹⁸ and R¹⁹ are combined together to represent ═O; R² represents halogen, SR¹² (wherein R¹² has the same significance as defined above) or NR¹³R¹⁴ (wherein R¹³ and R¹⁴ have the same significances as defined above); R⁷ represents hydrogen; and R⁸ represents acetyl can be prepared according to the following reaction step.

{In the formula, R^(2b) represents halogen, SR¹² (wherein R¹² has the same significance as defined above) or NR¹³R¹⁴ (wherein R¹³ and R¹⁴ have the same significances as defined above).}

The halogen represented by R^(2b) has the same significance as the above halogen.

Step 9

Compound (IIIb) can be obtained by subjecting Compound (IIIa) obtained in step 8 to the reaction similar to that in step 3, step 4 or step 5.

Compound (IIIa) and Compound (IIIb) obtained in step 8 and step 9 can be used as intermediates for further synthesizing novel derivatives. For example, Compound (IIIc), wherein R^(2b) is converted into substituted or unsubstituted lower alkynyl (the lower alkynyl has the same significance as defined above), can be obtained by reaction of Compound (IIIba), i.e., the above Compound (IIIb) wherein R^(2b) is bromine, with substituted or unsubstituted lower alkyne (the lower alkyne includes acetylene, propyne, butyne, pentyne and hexyne having 2-6 carbon atoms) in the presence of an appropriate palladium catalyst according to the method described in the literature [SYNTHESIS, p. 235 (1991)] or a similar method thereto. Further, Compound (IIId), wherein R^(2b) is converted into substituted or unsubstituted aryl or substituted or unsubstituted heteroaryl, can also be obtained by reaction of Compound (IIIba) with various aromatic borate compounds or organic tin compounds instead of lower alkyne, which is known as the Suzuki reaction or the Stille reaction.

Compound (IIIe), wherein R^(2b) is converted into substituted or unsubstituted lower alkyl, can be obtained by subjecting the above Compound (IIIc) to catalytic hydrogenation in an inert solvent in the presence of an appropriate catalyst. As the inert solvent, lower alcohols such as methanol and ethanol, ethyl acetate, dimethylformamide, etc. may be used alone or as a mixture. As the catalyst, any of the catalysts that are usually used in hydrogenation, for example, palladium/carbon and platinum oxide can be used. The reaction is carried out at a temperature between 0° C. and the boiling point of the solvent used, preferably 20-30° C. for 0.5-48 hours.

Compound (IIIf), wherein R^(2b) is converted into substituted or unsubstituted lower alkenyl, can be obtained by using, as a catalyst, lead-treated palladium-calcium carbonate known as the Lindlar catalyst.

Any of these compounds wherein R¹ represents COCH₂CH(OCH₃)₂ can be converted into a compound wherein the carbonyl group in R¹ is reduced, R¹⁸ represents hydrogen and R¹⁹ represents hydroxy by reducing the compound wherein R¹ represents COCH₂CH(OCH₃)₂ with 0.5-10 equivalents of sodium borohydride in an inert solvent. As the inert solvent, lower alcohols such as methanol and ethanol, dichloromethane, chloroform, dimethylformamide, etc. may be used alone or as a mixture. The reaction is carried out at a temperature between −20° C. and the boiling point of the solvent used, preferably 0-30° C. for 0.1-12 hours.

Process 10

Compound (IV), i.e., Compound (I) wherein R¹ represents:

(wherein n has the same significance as defined above); R², R⁴, R⁵ and R⁶ represent hydrogen; R²′ and R³ are combined together to represent a bond; R⁷ represents hydrogen; and R⁸ represents acetyl can be prepared according to the following reaction step.

(In the formula, n has the same significance as defined above.)

Step 10

Compound (IV) can be obtained by reaction of LK6-A with 1-100 equivalents of ethylene glycol or propylene glycol in an inert solvent, if necessary, in the presence of a base.

As the inert solvent, halogen solvents such as dichloromethane and chloroform, ethers such as tetrahydrofuran and dioxane, dimethyl sulfoxide, dimethylformamide, etc. may be used. Ethylene glycol or propylene glycol may be used also as the solvent.

As the base, sodium carbonate, potassium carbonate, sodium hydroxide, potassium hydroxide, 1,4-diazabicyclo[2.2.2]octane, 1,8-diazabicyclo[5.4.0]undec-7-ene, triethylamine, diisopropylethylamine, etc. may be used in an amount of 0.1-20 equivalents based on LK6-A. The reaction is carried out at a temperature between 0° C. and the boiling point of the solvent used, preferably 20-60° C. for 1-96 hours.

Process 11

Compound (V), i.e., Compound (I) wherein R¹ represents (E)-3-methoxyacryloyl; R² represents hydrogen; R²′ and R³ are combined together to represent a bond; R⁴ represents hydrogen; R⁵ represents substituted or unsubstituted lower alkoxycarbonyl or substituted or unsubstituted aralkyloxycarbonyl; R⁷ represents hydrogen; and R⁸ represents acetyl can be prepared according to the following reaction step.

(In the formula, R²⁰ represents substituted or unsubstituted lower alkoxy or substituted or unsubstituted aralkyloxy.)

The substituted or unsubstituted lower alkoxy and substituted or unsubstituted aralkyloxy represented by R²⁰ have the same significances as the above substituted or unsubstituted lower alkoxy and substituted or unsubstituted aralkyloxy, respectively.

Step 11

Compound (V) can be obtained by reaction of LK6-A with 1-5 equivalents of ClCOR²⁰ (wherein R²⁰ has the same significance as defined above) in an inert solvent in the presence of a base.

As the inert solvent, dichloromethane, chloroform, methanol, ethanol, dimethylformamide, etc. may be used alone or as a mixture.

As the base, 1,4-diazabicyclo[2.2.2]octane, 1,8-diazabicyclo[5.4.0]undec-7-ene, triethylamine, diisopropylethylamine, etc. may be used in an amount of 1-5 equivalents based on LK6-A. The reaction is carried out at 0-50° C. for 0.1-12 hours.

Process 12

Compound (VI), i.e., Compound (I) wherein R¹ represents COCHR¹⁵CH(OCH₃)₂ (wherein R¹⁵ represents lower alkyl); R² represents hydrogen, halogen, SR¹² (wherein R¹² has the same significance as defined above) or NR¹³R¹⁴ (wherein R¹³ and R¹⁴ have the same significances as defined above); R²′ and R³ are combined together to represent a bond; R⁴ and R⁵, which may be the same or different, each represents hydrogen or lower alkyl; R⁷ represents hydrogen or lower alkyl; and R⁸ represents acetyl can be prepared according to the following reaction step.

(In the formula, R^(4a) and R^(5a), which may be the same or different, each represents hydrogen or lower alkyl; R^(7a) represents hydrogen or lower alkyl; and R^(2a) and R¹⁵ have the same significances as defined above.)

The lower alkyl represented by R^(4a), R^(5a) and R^(7a) has the same significance as the above lower alkyl.

Step 12

Compound (VI) can be obtained by reaction of Compound (IIIa) or (IIIb) with 1-10 equivalents of halogenated lower alkyl represented by R^(15b)X² (wherein R^(15b) represents lower alkyl, and X² represents halogen, and the lower alkyl represented by R^(15b) and the halogen represented by X² have the same significances as the above lower alkyl and halogen, respectively) in an inert solvent in the presence of 1-10 equivalents of a base.

Examples of the inert solvent include tetrahydrofuran, dioxane and dimethylformamide, and examples of the base include potassium carbonate, sodium hydride, potassium tert-butoxide and lithium diisopropylamide.

The reaction is carried out at a temperature between −78° C. and the boiling point of the solvent used, preferably 0-30° C. for 0.5-12 hours.

Process 13

Compound (VII), i.e., Compound (I) wherein R¹ represents COCX³HCH(OCH₃)₂ (wherein X³ represents halogen, and the halogen represented by X³ has the same significance as the above halogen); R² represents hydrogen, halogen, SR¹² (wherein R¹² has the same significance as defined above) or NR¹³R¹⁴ (wherein R¹³ and R¹⁴ have the same significances as defined above); R²′, and R³ are combined together to represent a bond; R⁴ and R⁵ represent hydrogen; R⁶ represents hydrogen or halogen; R⁷ represents hydrogen; and R⁸ represents acetyl can be prepared according to the following reaction step.

(In the formula, X³, R⁶ and R^(2a) have the same significances as defined above.)

Step 13

Compound (VII) can be obtained by reaction of Compound (IIIa) or (IIIb) with 1-10 equivalents of a halogenating reagent in an inert solvent, if necessary, in the presence of 1-10 equivalents of a base.

Examples of the base include triethylamine, diisopropylethylamine, potassium carbonate and sodium carbonate. Examples of the halogenating reagent include bromine, chlorine, iodine, N-chlorosuccinimide, N-bromosuccinimide, N-iodosuccinimide, tetrabutylammonium tribromide and pyrrolidone hydrotribromide.

As the inert solvent, dichloromethane, chloroform, carbon tetrachloride, methanol, ethanol, tetrahydrofuran, dioxane, dimethylformamide, etc. may be used alone or as a mixture. The reaction is carried out at a temperature between 0° C. and the boiling point of the solvent used, preferably 20-30° C. for 0.5-24 hours.

Process 14

Compound (VIII), i.e., Compound (I) wherein R¹ represents 1-hydroxy-3-methoxypropyl; R² represents hydrogen, halogen, SR¹² (wherein R¹² has the same significance as defined above) or NR¹³R¹⁴ (wherein R¹³ and R¹⁴ have the same significances as defined above); R²′ and R³ are combined together to represent a bond; R⁴ and R⁵ represent hydrogen; R⁶ represents hydrogen; R⁷ represents hydrogen; and R⁸ represents acetyl can be prepared according to the following reaction step.

(In the formula, R^(2a) has the same significance as defined above.)

Step 14

Compound (VIII) can be obtained by reducing LK6-A or Compound (IIe) with 1-10 equivalents of sodium borohydride in an inert solvent.

As the inert solvent, lower alcohols such as methanol and ethanol, dichloromethane, chloroform, dimethylformamide, etc. may be used alone or as a mixture.

The reaction is carried out at a temperature between −20° C. and the boiling point of the solvent used, preferably 0-30° C. for 0.1-12 hours.

Process 15

Compound (IX), i.e., Compound (I) wherein R¹ represents (E)-3-methoxyacryloyl or COCH₂CH(OCH₃)₂; R² represents hydrogen or substituted or unsubstituted lower alkanoyloxy; R²′ represents hydrogen; R³ represents substituted or unsubstituted lower alkanoyl; R⁴ represents hydrogen; R⁵ represents substituted or unsubstituted lower alkanoyl; R⁶ represents hydrogen; R⁷ represents hydrogen; and R⁸ represents acetyl can be prepared according to the following reaction step.

[In the formula, R^(1a) represents (E)-3-methoxyacryloyl or COCH₂CH(OCH₃)₂; R^(2c) represents hydrogen or substituted or unsubstituted lower alkanoyloxy; and R²¹ represents substituted or unsubstituted lower alkyl.]

The substituted or unsubstituted lower alkanoyloxy represented by R^(2c) has the same significance as the above substituted or unsubstituted lower alkanoyloxy, and the substituted or unsubstituted lower alkyl represented by R²¹ has the same significance as the above substituted or unsubstituted lower alkyl.

Step 15

Compound (IX) can be obtained by reaction of LK6-A or Compound (IIIa) with 2-100 equivalents of an acid anhydride, if necessary, in an inert solvent.

Examples of the inert solvent include dichloromethane, chloroform and dimethylformaimde, and the acid anhydride may be used also as the solvent. The reaction is carried out at a temperature between 0° C. and the boiling point of the solvent used, preferably 20-30° C. for 1-72 hours.

Further conversion of R^(2c) is possible using Compound (IX) obtained in step 15 as a synthetic intermediate. For example, Compound (IXa), i.e., Compound (IX) wherein R^(2c) is hydrogen can be obtained by hydrogenating the compound wherein R^(2c) is lower alkanoyloxy in an inert solvent in the presence of an appropriate catalyst. As the inert solvent, lower alcohols such as methanol and ethanol, ethyl acetate, dimethylformamide, etc. may be used alone or as a mixture. Appropriate catalysts include those conventionally used in hydrogenation, for example, palladium/carbon and platinum oxide.

The reaction is carried out at a temperature between 0° C. and the boiling point of the solvent used, preferably 20-30° C. for 0.5-48 hours.

The above Compounds (I)-(IX) can be obtained by appropriately combining the above-described methods. Further, Compounds (I) described in the present invention can be obtained by combining methods conventionally used in synthetic organic chemistry.

The desired compounds in the processes described above can be purified by appropriate combinations of purification methods conventionally used in synthetic organic chemistry, for example, filtration, extraction, washing, drying, concentration, crystallization and various kinds of chromatography. The intermediates may be subjected to the subsequent reaction without purification.

In the case where a salt of Compound (I) is desired and it is produced in the form of the desired salt, it can be subjected to purification as such. In the case where Compound (I) is produced in the free state and its salt is desired, the salt can be formed according to a conventional method, that is, by dissolving or suspending Compound (I) in a suitable solvent and adding a desired acid or base thereto.

Compounds (I) and pharmaceutically acceptable salts thereof may exist in the form of adducts with water or various solvents, which are also within the scope of the present invention.

Compounds (I) and pharmaceutically acceptable salts thereof can be used as such or in various pharmaceutical forms according to the pharmacological activity and the purpose of administration. Pharmaceutical compositions of the present invention can be prepared by uniformly mixing an effective amount of Compound (I) or a pharmaceutically acceptable salt thereof, as an active ingredient, with a pharmaceutically acceptable carrier. The carrier can take a wide variety of forms according to the pharmaceutical form desirable for administration. These pharmaceutical compositions are preferably in a unit dose form suitable for oral administration or parenteral administration in the form of ointment, injection, or the like.

Tablets can be prepared using excipients such as lactose, glucose, sucrose, mannitol and methyl cellulose, disintegrating agents such as starch, sodium alginate, calcium carboxymethyl cellulose and crystalline cellulose, lubricants such as magnesium stearate and talc, binders such as gelatin, polyvinyl alcohol, polyvinyl pyrrolidone, hydroxypropyl cellulose and methyl cellulose, surfactants such as sucrose fatty acid ester and sorbitol fatty acid ester, and the like in a conventional manner. It is preferred that each tablet contains 1-300 mg of the active ingredient.

Granules can be prepared using excipients such as lactose and sucrose, disintegrating agents such as starch, binders such as gelatin, and the like in a conventional manner. Powders can be prepared using excipients such as lactose and mannitol, and the like in a conventional manner. Capsules can be prepared using gelatin, water, sucrose, gum arabic, sorbitol, glycerin, crystalline cellulose, magnesium stearate, talc, and the like in a conventional manner. It is preferred that each capsule contains 1-300 mg of the active ingredient.

Syrup can be prepared using sugars such as sucrose, water, ethanol, and the like in a conventional manner.

Ointment-can be prepared using ointment bases such as vaseline, liquid paraffin, lanolin and macrogol, emulsifiers such as sodium lauryl lactate, benzalkonium chloride, sorbitan mono-fatty acid ester, sodium carboxymethyl cellulose and gum arabic, and the like in a conventional manner.

Injections can be prepared using solvents such as water, physiological saline, vegetable oils (e.g., olive oil and peanut oil), ethyl oleate and propylene glycol, solubilizing agents such as sodium benzoate, sodium salicylate and urethane, isotonicity agents such as sodium chloride and glucose, preservatives such as phenol, cresol, p-hydroxybenzoic acid ester and chlorobutanol, antioxidants such as ascorbic acid and sodium pyrosulfite, and the like in a conventional manner.

Compounds (I) and pharmaceutically acceptable salts thereof can be administered orally or parenterally as an ointment, injection, or the like. The effective dose and the administration schedule of Compound (I) or a pharmaceutically acceptable salt thereof will vary depending on the mode of administration, the patient's age, body weight and condition, etc. However, it is generally preferred to administer Compound (I) or a pharmaceutically acceptable salt thereof in a dose of 0.01-20 mg/kg 1-4 times a day.

Examples of Compounds (I) obtained by the present invention are shown in Tables 1 and 2.

TABLE 1

Compound Example No. No. R¹ R² 1 1

H 2 2

H 3 3

N(CH₃)₂ 4 4

H 5 5

H 6 5

7 6

H 8 7

H 9 8

H 10 9

H

Compound Example No. No. R¹ 11 10

12 11

13 12

14 13

15 14

16 15

17 16

Compound Example No. No. R¹ R² 18 17

19 18

20 19

SCH₂CH₃ 21 20

22 21

Cl 23 22

Br 24 23

I 25 24

H

Compound Example No. No. R¹ R⁷ R⁸ 26 25

H H 27 26

H H 28 27

H COCH₃ 29 28

H H 30 29

H COCH₃ 31 30

H COCH₃ 32 30

H H 33 31

H COCH₃ 34 31

H H

Compound Example No. No. R¹ R⁵ R⁴ R⁸ R⁷ 35 32

CO₂CH₃ H COCH₃ H 36 33

CO₂CH₂CH₃ H COCH₃ H 37 34

CO₂(CH₂)₂CH₃ H COCH₃ H 38 35

CO₂(CH₂)₃CH₃ H COCH₃ H 39 36

CO₂(CH₂)₇CH₃ H COCH₃ H 40 37

CO₂CH₂Ph H COCH₃ H 41 38

CH₃ CH₃ COCH₃ CH₃ 42 39

CH₃ CH₃ CH₃ CH₃ 43 39

CH₃ CH₃ CH₃ CH₃

Compound Example No. No. R¹ R² 44 40

Br 45 41

N(CH₃)₂ 46 42

N(CH₃)₂ 47 43

48 44

49 45

50 46

51 47

N₃ 52 48

N₃ 53 49

54 50

Compound Example No. No. R¹ R² 55 51

56 52

57 53

58 54

59 55

NH(CH₂)₃CH₃ 60 56

NH(CH₂)₃CH₃ 61 57

62 58

63 59

64 60

Compound Example No. No. R¹ R² 65 61

N(CH₂CH₃)₂ 66 62

N(CH₂CH₃)₂ 67 63

68 64

69 65

70 66

71 67

NHCH₂CH₂OCH₃ 72 68

NHCH₂CH₂OCH₃ 73 69

74 70

Compound Example No. No. R¹ R² R⁶ R⁷ R⁸ 75 71

CH₂CH₃ H H COCH₃ 76 72

COCH₃ H H COCH₃ 77 73

CH₂CH₃ H H COCH₃ 78 74

Br H H H 79 74

Br Br H H 80 75

H Br H H 81 76

Br H H COCH₃ 82 77

Br Br H COCH₃ 83 78

Br H H COCH₃ 84 79

Br H H H 85 80

H H H H 86 81

H H H H 87 82

H H H H 88 83

H H H H

Compound Example No. No. R¹ 89 84

90 85

91 86

92 87

93 88

94 89

95 90

96 91

97 92

98 93

99 94

100 95

101 96

102 97

103 98

104 99

Compound Example No. No. R¹ 105 100

106 101

107 102

108 103

109 104

Ph:

Ac: COCH₃

TABLE 2

Compound Example No. No. R¹ R² 110 105

OCOCH₃ 111 106

OCOCH₃ 112 107

H 113 107

H 114 108

H

The immunosuppressive activity of typical Compounds (I) is described below.

TEST EXAMPLE 1 Growth Inhibition Against T Cells in Mixed Mouse Lymphocyte Reaction

Lymph node was aseptically excised from a B10.BR mouse (Japan SLC Inc.) and washed with a solution comprising Hanks' balanced salt solution (HBSS, Gibco) and 2.5% fetal calf serum (FCS, Gibco) (HBSS-FCS). To the washed lymph node was added RPMI1640 medium comprising 10% FCS, 1% 200 mM L-glutamine, a 1% penicillin-streptomycin solution, 5% NCTC-109, 1% 1 M HEPES (all produced by Gibco), 7.5% sodium hydrogen carbonate and 0.1% 50 mM 2-mercaptoethanol (hereinafter referred to as RPMI1640-FCS) to prepare a single cell suspension having a density of 3×10⁶ cells/ml.

Separately, spleen was aseptically excised from an AKR mouse (Japan SLC Inc.) to prepare a single cell suspension with HBSS-FCS. To the obtained cell suspension was added mitomycin C (MMC) (Kyowa Hakko Kogyo Co., Ltd.) to a final concentration of 0.05 mg/ml, followed by incubation at 37° C. for 30 minutes. Then, the suspension was washed three times with HBSS-FCS, and a single cell suspension having a density of 1×10⁷ cells/ml was prepared using RP1640-FCS.

Into each well of a 96-well microtiter plate were put 0.05 ml of the B10. BR mouse lymph node cell suspension (containing 1.5×10⁵ cells), 0.05 ml of the AKR mouse spleen cell suspension (containing 5×10⁵ cells) and 0.1 ml of a solution of Compound (I) in RPMI1640-FCS at each test concentration, followed by incubation in a CO₂ incubator at 37° C. for 72 hours. The solutions of the test compound were prepared to give final concentrations of 7×10⁻¹⁰-7×10⁻⁶ M.

[³H]-Thymidine was added to the wells in an amount of 1×10⁻⁶ Ci, 18 hours before the end of incubation. After the incubation, the cells were collected on filter paper with a cell harvester, followed by drying. A toluene scintillator was added to the cells, and the radioactivity of [³H]-thymidine incorporated into the cells was determined using a liquid scintillation counter (test group).

As a control group, 0.1 ml of RPMI1640-FCS containing no test compound was added, followed by incubation in the same manner as above, and the radioactivity of [³H]-thymidine incorporated into the cells was determined. To 0.05 ml of the B10.BR mouse lymph node cell suspension (containing 1.5×10⁵ cells) or 0.05 ml of the AKR mouse spleen cell suspension (containing 5×10⁵ cells) was added 0.15 ml of RPMI1640-FCS, followed by incubation in the same manner as above, and the radioactivity of [³H]-thymidine incorporated into the cells was determined.

The T cell growth inhibition rate was calculated according to the following equation.

T cell growth inhibition rate (%)=(C−T)/{C−(A+B)}×100

C: Radioactivity of the control group

T: Radioactivity of the test group

A: Radioactivity of the MMC-treated AKR mouse

B: Radioactivity of the B10.BR mouse

(In the equation, the radioactivity of the MMC-treated AKR mouse refers to the radioactivity of [³H]-thymidine incorporated, into the MMC-treated AKR mouse spleen cells, and the radioactivity of the B10.BR mouse refers to the radioactivity of [³H]-thymidine incorporated into the B10.BR mouse lymph node cells.)

The 50% inhibitory concentration of each compound against the growth of T cells in mixed mouse lymphocyte reaction was calculated from the above equation. The results are shown in Table 3.

TABLE 3 Compound 50% Inhibitory No. concentration (μM) 1 0.018 2 0.25 4 0.25 5 0.098 7 0.048 8 0.058 9 0.38 10 0.15 11 0.072 12 0.050 13 0.058 14 0.044 15 0.038 20 0.68 22 0.15 23 0.65 24 0.45 25 0.032 27 0.11 31 0.0090 32 0.41 33 0.42 50 0.46 52 0.091 73 0.54 74 0.16 76 0.20 88 0.88 94 0.88

TEST EXAMPLE 2 Effect on Delayed Type Hypersensitivity of Sole

Balb/c strain male mice (8-weeks-old, Charles River) were immunized by subcutaneous administration of 0.1 ml of 2,4,6-trinitrobenzene sulfonic acid (TNBS) (adjusted to 10 mM with a phosphate buffer) into the right side. The test was carried out using groups of mice, each group consisting of 5 animals, which are a control group treated with 0.3% methyl cellulose containing 3% DMSO, a group treated with a fixed concentration of a test compound suspended in 0.3% methyl cellulose containing 3% DMSO, and a group treated with cyclosporin A (Sandoz Pharmaceuticals, Ltd.).

The 0.3% methyl cellulose containing 3% DMSO or the test compound was intraperitoneally administered to the mice 30 minutes before the immunization treatment and thereafter every 24 hours, totally 5 times. Cyclosporin A was orally administered one hour before the immunization treatment and thereafter every 24 hours, totally 5 times. On the fifth day when sensitization was established, 0.05 ml of the above 10 mM TNBS as a causative antigen was subcutaneously injected into the right hind sole. Eighteen hours after the injection, the thickness of both feet of each mouse of the groups treated with respective amounts of test compound was measured with Dial Thickness Gauge. The value (T) was obtained by subtracting the thickness of the left foot from that of the right foot. Separately the thickness of both feet of each mouse of the group treated with no test compound was measured and the value (C) was obtained by subtracting the thickness of the left foot from that of the right foot. The suppression rate (%) was determined according to the equation [(C−T)/C]×100 (%). The results are shown in Table 4.

TABLE 4 Compound Dose Suppression rate No. (mg/kg) (%) 25 30 77 Cyclosporin A 30 83

As can be seen from Tables 3 and 4, Compounds (I) have an excellent immunosuppressive activity and are useful as therapeutic agents for autoimmune diseases, allergic diseases, infections caused by organ transplantation, etc. Compounds (I) are also useful as therapeutic agents for diseases caused by abnormal cell growth such as leukemia and cancers.

BEST MODES FOR CARRYING OUT THE INVENTION

Certain embodiments of the present invention are illustrated in the following examples.

The physicochemical properties of the compounds shown in examples below were determined using the following instruments.

¹H NMR:

JEOL Alpha 400 (400 MHz)

JEOL Lambda 300 (300 MHz)

Bruker DMX-500 (500 MHz)

FABMS:

JEOL JMS-HX110

The peak (δ) in the proton nuclear magnetic resonance spectrum (¹H NMR) used in examples is expressed in unit of 1/1000000 (ppm) toward lower magnetic field from tetramethylsilane. The observed form, the coupling constant and the number of proton are shown, in the order given, in the parenthesis after the value of δ of each signal. In the ¹H NMR data, br means that the signal is broad.

EXAMPLE 1 Compound 1

LK6-A (48.0 mg, 0.15 mmol) was dissolved in dimethyl sulfoxide (8 ml), and 28% aqueous ammonia (0.15 ml) was added thereto, followed by stirring at room temperature for 14 hours. After the reaction mixture was diluted with chloroform, the resulting diluted solution was passed through a silica gel column for adsorption, followed by elution with chloroform/methanol (93:7), whereby Compound 1 (38.0 mg, 83%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 2.34 (s, 3H), 6.81 (d, J=7.3 Hz, 1H), 7.25 (ddd, J=14.6, 7.3, 7.3 Hz, 1H), 7.77 (br dd, J=7.3, 5.7 Hz, 1H), 8.02 (br s, 2H), 8.10 (s, 1H), 8.34 (s, 1H), 8.59 (s, 1H), 9.46 (br dd, J=14.6, 5.7 Hz, 1H), 9.94 (br s, 1H)

FABMS m/z 296 (M+H)⁺ C₁₅H₁₃N₅O₂=295.

EXAMPLE 2 Compound 2

LK6-A (39.1 mg, 0.13 mmol) was dissolved in dimethyl sulfoxide (8 ml), and 50% aqueous dimethylamine (0.16 ml) was added thereto, followed by stirring at room temperature for 3.5 hours. To the reaction mixture was added water, and the resulting mixture was extracted with chloroform. The organic layer was washed twice with water and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol (9:1), whereby Compound 2 (24.8 mg, 61%) was obtained.

¹H NMR (500 MHz, DMSO-d₆) δ 2.34 (s, 3H), 3.06 (br s, 3H), 3.19 (br s, 3H), 6.93 (br d, J=12.7 Hz, 1H), 7.83 (d, J=12.7 Hz, 1H), 8.01 (br s, 2H), 8.11 (s, 1H), 8.34 (s, 1H), 8.60 (s, 1H), 10.1 (br s, 1H)

FABMS m/z 324 (M+H)⁺ C₁₇H₁₇N₅O₂=323.

EXAMPLE 3 Compound 3

LK6-A (20.5 mg, 0.07 mmol) was dissolved in dimethyl sulfoxide (6 ml), and 50% aqueous dimethylamine (2 ml) was added thereto, followed by stirring at room temperature for 2.5 hours. To the reaction mixture was added water, and the resulting mixture was extracted three times with chloroform. The organic layers were combined and dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol (9:1), whereby Compound 3 (16.0 mg, 66%) was obtained.

¹H NMR (500 MHz, CDCl₃) δ 2.37 (s, 3H), 3.06 (br s, 3H), 3.22 (br s, 3H), 3.47 (s, 6H), 4.85 (br s, 2H), 6.63 (d, J=12.6 Hz, 1H), 7.96 (d, J=12.6 Hz, 1H), 8.15 (s, 1H), 8.70 (s, 1H), 9.04 (br s, 1H)

FABMS m/z 367 (M+H)⁺ C₁₉H₂₂N₆O₂=366.

EXAMPLE 4 Compound 4

LK6-A (100 mg, 0.31 mmol) was dissolved in dimethyl sulfoxide (10 ml), and diethylamine (0.096 ml, 0.93 mmol) was added thereto, followed by stirring at room temperature for 50 minutes. To the reaction mixture was added water, and the resulting mixture was extracted with chloroform. The organic layer was washed with water and a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol (14:1) and preparative thin layer chromatography with chloroform/methanol (9:1), followed by trituration with isopropyl ether, whereby Compound 4 (47.0 mg, 43%) was obtained.

¹H NMR (500 MHz, DMSO-d₆) δ 1.1-1.2 (m, 6H), 2.28 (s, 3H), 3.3-3.5 (m, 4H), 6.90 (br d, J=12.7 Hz, 1H), 7.77 (d, J=12.9 Hz, 1H), 7.97 (br s, 2H), 8.02 (s, 1H), 8.30 (s, 1H), 8.54 (s, 1H), 9.97 (s, 1H)

FABMS m/z 352 (M+H)⁺ C₁₉H₂₁N₅O₂=351.

EXAMPLE 5 Compounds 5 and 6

LK6-A (29.8 mg, 0.10 mmol) was dissolved in dimethyl sulfoxide (6 ml), and piperidine (0.050 ml) was added thereto, followed by stirring at room temperature for 15 hours. To the reaction mixture was added water, and the resulting mixture was extracted with chloroform. The organic layer was washed twice with water and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol/triethylamine (97:1:2), whereby Compound 5 (16.2 mg, 46%) and Compound 6 (11.0 mg, 26%) were obtained.

Compound 5: ¹H NMR (400 MHz, DMSO-d₆) δ 1.64 (m, 6H), 2.36 (s, 3H), 3.54 (m, 4H), 7.05 (d, J=12.9 Hz, 1H), 7.82 (d, J=12.9 Hz, 1H), 8.16 (s, 1H), 8.31 (br s, 2H), 8.43 (s, 1H), 8.67 (s, 1H), 10.2 (s, 1H)

FABMS m/z 364 (M+H)⁺ C₂₀H₂₁N₅O₂=363.

Compound 6: ¹H NMR (400 MHz, CD₃OD) δ 1.76 (m, 6H), 1.81 (m, 6H), 2.33 (s, 3H), 3.6 (m, 4H), 3.9 (m, 4H), 6.79 (d, J=12.7 Hz, 1H), 8.01 (d, J=12.7 Hz, 1H), 8.08 (s, 1H), 8.61 (s, 1H)

FABMS m/z 447 (M+H)⁺ C₂₅H₃₀N₆O₂=446.

EXAMPLE 6 Compound 7

LK6-A (31.0 mg, 0.10 mmol) was dissolved in dimethyl sulfoxide (6 ml), and N-methylpiperazine (0.050 ml) was added thereto, followed by stirring at room temperature for 3.5 hours. To the reaction mixture was added water, and the resulting mixture was extracted with chloroform. The organic layer was washed twice-with water and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol (4:1), whereby Compound 7 (28.0 mg, 74%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 2.24 (s, 3H), 2.35 (s, 3H), 2.43 (m, 4H), 3.56 (m, 4H), 7.09 (d, J=12.8 Hz, 1H), 7.80 (d, J=12.8 Hz, 1H), 8.01 (br s, 2H), 8.13 (s, 1H), 8.34 (s, 1H), 8.61 (s, 1H), 10.1 (s, 1H)

FABMS m/z 379 (M+H)⁺ C₂₀H₂₂N₆0₂=378.

EXAMPLE 7 Compound 8

LK6-A (29.9 mg, 0.10 mmol) was dissolved in dimethyl sulfoxide (6 ml), and morpholine (0.050 ml) was added thereto, followed by stirring at room temperature for 5 hours. To the reaction mixture was added water, and the resulting mixture was extracted with chloroform. The organic layer was washed twice with water and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol/triethylamine (97:1:2), whereby Compound 8 (24.8 mg, 70%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 2.37 (s, 3H), 3.60 (m, 4H), 3.71 (m, 4H), 7.12 (d, J=12.8 Hz, 1H), 7.87 (d, J=12.8 Hz, 1H), 8.23 (s, 1H), 8.61 (s, 1H), 8.78 (s, 1H), 8.92 (br s, 2H), 10.3 (s, 1H)

FABMS m/z 366 (M+H)⁺ C₁₉H₁₉N₅O₃=365.

EXAMPLE 8 Compound 9

LK6-A (49.1 mg, 0.16 mmol) was dissolved in dimethyl sulfoxide (10 ml), and dibenzylamine (0.10 ml) was added thereto, followed by stirring at room temperature for 48 hours. To the reaction mixture was added water, and the resulting mixture was extracted with chloroform. The organic layer was washed twice with water and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol (39:1), whereby Compound 9 (55.4 mg, 74%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 2.27 (s, 3H), 4.67 (s, 2H), 4.70 (s, 2H), 7.18 (d, J=12.9 Hz, 1H), 7.2-7.4 (m, 1H), 8.04 (br s, 2H), 8.06 (s, 1H), 8.12 (d, J=12.9 Hz, 1H), 8.33 (s, 1H), 8.59 (s, 1H), 9.92 (s, 1H)

FABMS m/z 476 (M+H)⁺ C₂₉H₂₅N₅O₂=475.

EXAMPLE 9 Compound 10

LK6-A (28.8 mg, 0.09 mmol) was dissolved in dimethyl sulfoxide (6 ml), and diethanolamine (0.050 ml) was added thereto, followed by stirring at room temperature for 15 hours. The reaction mixture was diluted with chloroform, and the resulting diluted solution was passed through a silica gel column for adsorption, followed by elution with chloroform/methanol (4:1), whereby Compound 10 (25.6 mg, 72%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 2.32 (s, 3H), 3.5-3.8 (m, 8H), 4.8-4.9 (m, 2H), 6.93 (br d, J=13 Hz, 1H), 7.81 (d, J=12.9 Hz, 1H), 8.01 (br s, 2H), 8.06 (s, 1H), 8.34 (s, 1H), 8.57 (s, 1H), 9.93 (s, 1H)

FABMS m/z 384 (M+H)⁺ C₁₉H₂₁N₅O₄=383.

EXAMPLE 10 Compound 11

LK6-A (60 mg, 0.19 mmol) was dissolved in dimethyl sulfoxide (4 ml), and ethanolamine (0.030 ml, 0.50 mmol) was added thereto, followed by stirring at room temperature for 24 hours. Then, the reaction mixture was poured into water (200 ml) and the resulting mixture was allowed to stand at 5° C. for 3 days for precipitation. The precipitate was separated by filtration through a membrane filter, whereby Compound 11 (35.4 mg, 54%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 2.34 (s, 3H), 3.4-3.5 (m, 2H), 3.55 (dd, J=10.5, 5.2 Hz, 2H), 4.90 (t, J=5.2 Hz, 1H), 6.79 (d, J=7.6 Hz, 1H), 7.28 (dd, J=13.1, 7.6 Hz, 1H), 8.00 (br s, 2H), 8.10 (s, 1H), 8.34 (d, J=1.0 Hz, 1H), 8.58 (d, J=1.0 Hz, 1H), 9.95 (s, 1H), 10.2-10.4 (m, 1H)

FABMS m/z 340 (M+H)⁺ C₁₇H₁₇N₅O₃=339.

EXAMPLE 11 Compound 12

LK6-A (60 mg, 0.19 mmol) was dissolved in dimethyl sulfoxide (4 ml), and 0.32 ml of an aqueous solution of galactosamine hydrochloride (109.2 mg, 0.51 mmol) and potassium carbonate (36 mg, 0.26 mmol) was added thereto, followed by stirring at room temperature for 12 hours. Then, the reaction mixture was poured into water (200 ml) and the resulting mixture was allowed to stand at 5° C. for 3 days for precipitation. The precipitate was separated by filtration through a membrane filter and dissolved in dimethyl sulfoxide (1 ml), and chloroform (200 ml) was added thereto. The resulting mixture was purified by silica gel column chromatography with chloroform/methanol (82:18), whereby Compound 12 (47.8 mg, 54%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ [only major component (α-form) is shown] 2.34 (s, 3H), 3.4-3.6 (m, 4H), 3.78 (br s, 1H), 3.88 (t, J=6.4 Hz, 1H), 4.57 (t, J=5.7 Hz, 1H), 4.61 (d, J=4.6 Hz, 1H), 4.91 (d, J=7.3 Hz, 1H), 5.14 (t, J=3.9 Hz, 1H), 6.78 (d, J=7.5 Hz, 1H), 6.82 (d, J=4.6 Hz, 1H), 7.26 (dd, J=12.8, 7.5 Hz, 1H), 7.99 (s, 2H), 8.10 (s, 1H), 8.34 (d, J=1.9 Hz, 1H), 8.57 (d, J=1.9 Hz, 1H), 9.95 (s, 1H), 10.2 (dd, J=12.7, 9.8 Hz, 1H)

FABMS m/z 458 (M+H)⁺ C₂₁H₂₃N₅O₇=457.

EXAMPLE 12 Compound 13

LK6-A (60 mg, 0.19 mmol) was dissolved in dimethyl sulfoxide (4 ml), and 0.32 ml of an aqueous solution of glucosamine hydrochloride (109.2 mg, 0.51 mmol) and potassium carbonate (36 mg, 0.21 mmol) was added thereto, followed by stirring at room temperature for 12 hours. Then, the reaction mixture was poured into water (200 ml), and the resulting mixture was allowed to stand at 5° C. for 3 days for precipitation. The precipitate was separated by filtration through a membrane filter and dissolved in dimethyl sulfoxide (1 ml), and chloroform (200 ml) was added thereto. The resulting mixture was purified by silica gel column chromatography with chloroform/methanol (84:16), whereby Compound 13 (47.8 mg, 54%) was obtained.

α-form: β-form=3:1 (signal ratio) α-form: ¹H NMR (400 MHz, DMSO-d₆) δ 2.34 (s, 3H), 3.1-3.2 (m, 2H), 3.4-3.6 (m, 2H), 3.6-3.7 (m, 2H), 4.45 (t, J=5.9 Hz, 1H), 4.97 (d, J=5.6 Hz, 1H), 5.12 (t, J=4.1 Hz, 1H), 5.16 (d, J=6.1 Hz, 1H), 6.79 (d, J=7.6 Hz, 1H), 6.90 (d, J=4.1 Hz, 1H), 7.25 (dd, J=12.9, 7.6 Hz, 1H), 8.01 (br s, 2H), 8.10 (s, 1H), 8.34 (d, J=1.9 Hz, 1H), 8.57 (d, J=1.9 Hz, 1H), 9.90 (s, 1H), 10.2 (dd, J=12.9, 9.5 Hz, 1H) β-form: ¹H NMR (400 MHz, DMSO-d₆) δ 2.34 (s, 3H), 2.88 (dd, J=8.3, 18.1 Hz, 1H), 3.1-3.2 (m, 1H), 3.4-3.6 (m, 2H), 3.7-3.8 (m, 2H), 4.54 (t, J=5.8 Hz, 1H), 4.59 (t, J=7.7 Hz, 1H), 5.05 (d, J=5.4 Hz, 1H), 5.28 (d, J=6.1 Hz, 1H), 6.81 (d, J=8.5 Hz, 1H), 6.93 (d, J=7.7 Hz, 1H), 7.2-7.3 (m, 1H), 8.01 (br s, 2H), 8.10 (s, 1H), 8.34 (d, J=1.9 Hz, 1H), 8.57 (d, J=1.9 Hz, 1H), 9.90 (s, 1H), 10.2-10.3 (m, 1H)

FABMS m/z 458 (M+H)⁺ C₂₁H₂₃N₅O₇=457.

EXAMPLE 13 Compound 14

LK6-A (60 mg, 0.19 mmol) was dissolved in dimethyl sulfoxide (4 ml), and 0.32 ml of an aqueous solution of mannosamine hydrochloride (109.2 mg, 0.51 mmol) and potassium carbonate (36 mg, 0.21 mmol) was added thereto, followed by stirring at room temperature for 12 hours. Then, the reaction mixture was poured into water (300 ml), and the resulting mixture was allowed to stand at 5° C. for 3 days for precipitation. The precipitate was separated by filtration through a membrane filter and dissolved in dimethyl sulfoxide (1 ml), and chloroform (200 ml) was added thereto. The resulting mixture was purified by silica gel column chromatography with chloroform/methanol (82:18), whereby Compound 14 (51.0 mg, 57.6%) was obtained.

FABMS m/z 458(M+H)⁺ C₂H₂₃ N₅O₇=457.

EXAMPLE 14 Compound 15

LK6-A (60 mg, 0.19 mmol) was dissolved in dimethyl sulfoxide (4 ml), and 0.32 ml of an aqueous solution of D-glucamine (91.2 mg, 0.50 mmol) was added thereto, followed by stirring at room temperature for 12 hours. Then, the reaction mixture was poured into water (300 ml), and the resulting mixture was allowed to stand at5° C. for 3 days for precipitation. The precipitate was separated by filtration through a membrane filter and dissolved in dimethyl sulfoxide (1 ml), and chloroform (200 ml) was added thereto. The resulting mixture was purified by silica gel column chromatography with chloroform/methanol (82:18), whereby Compound 15 (49.0 mg, 55.0%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 2.34 (s, 3H), 3.2-3.7 (m, 8H), 4.3-4.5 (m, 4H), 4.97 (d, J=5.1 Hz, 1H), 6.78 (d, J=7.4 Hz, 1H), 7.26 (dd, J=13.0, 7.4 Hz, 1H), 8.01 (br s, 2H), 8.10 (s, 1H), 8.34 (d, J=1.0 Hz, 1H), 8.58 (d, J=1.0 Hz, 1H), 9.97 (s, 1H), 10.3-10.4 (m, 1H)

FABMS m/z 460 (M+H)⁺ C₂₁H₂₅N₅O₇=459.

EXAMPLE 15 Compound 16

LK6-A (60 mg, 0.19 mol) was dissolved in dimethyl sulfoxide (4 ml), and 0.3 ml of an aqueous solution of 1-amino-1-deoxy-β-D-galactose (173.4 mg, 0.97 mmol) was added thereto, followed by stirring at room temperature for 24 hours. Then, the reaction mixture was poured into water (200 ml), and the resulting mixture was allowed to stand at 5° C. for 3 days for precipitation. The precipitate was separated by filtration through a membrane filter and dissolved in dimethyl sulfoxide (1 ml), and chloroform (200 ml) was added thereto. The resulting mixture was purified by silica gel column chromatography with chloroform/methanol (84:16), whereby Compound 16 (32.7 mg, 37%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 2.36 (s, 3H), 3.3-3.6 (m, 5H), 3.6-3.8 (m, 1H), 4.33 (t, J=8.6 Hz, 1H), 4.49 (d, J=5.4 Hz, 1H), 4.63 (t, J=5.4 Hz, 1H), 4.80 (d, J=5.9 Hz, 1H), 5.24 (d, J=5.6 Hz, 1H), 6.94 (d, J=7.8 Hz, 1H), 7.35 (dd, J=12.6, 7.8 Hz, 1H), 8.06 (br s, 2H), 8.12 (s, 1H), 8.35 (d, J=3.4 Hz, 1H), 8.60 (d, J=3.4 Hz, 1H), 9.97 (s, 1H), 10.29 (dd, J=12.6, 8.7 Hz, 1H)

FABMS m/z 458 (M+H)⁺ C₂₁H₂₃N₅O₇=457.

EXAMPLE 16 Compound 17

LK6-A (60 mg, 0.19 mmol) was dissolved in dimethyl sulfoxide (4 ml), and 0.3 ml of an aqueous solution of 1-amino-1-deoxy-β-D-glucose (173.4 mg, 0.97 mmol) was added thereto, followed by stirring at room temperature for 24 hours. Then, the reaction mixture was poured into water (200 ml), and the resulting mixture was allowed to stand at 5° C. for 3 days for precipitation. The precipitate was separated by filtration through a membrane filter and dissolved in dimethyl sulfoxide (1 ml), and chloroform (200 ml) was added thereto. The resulting mixture was purified by silica gel column chromatography with chloroform/methanol (84:16), whereby Compound 17 (27.4 mg, 31%) was obtained.

¹H NMR (400 MHz, DMSO-d 6) δ 2.35 (s, 3H), 3.0-3.2 (m, 2H), 3.2-3.3 (m, 1H), 3.4-3.5 (m, 2H), 3.6-3.7 (m, 1H), 4.40 (d, J=8.6 Hz, 1H), 4.57 (d, J=6.0 Hz, 1H), 4.99 (d, J=5.4 Hz, 1H), 5.06 (d, J=4.9 Hz, 1H), 5.41 (d, J=5.6 Hz, 1H), 6.96 (d, J=7.8 Hz, 1H), 7.37 (dd, J=12.3, 7.9 Hz, 1H), 8.07 (br s, 2H), 8.12 (s, 1H), 8.35 (s, 1H), 8.59 (s, 1H), 9.98 (s, 1H), 10.3 (dd, J=12.3, 8.6 Hz, 1H)

FABMS m/z 458 (M+H)⁺ C₂₁H₂₃N₅O₇=457.

EXAMPLE 17 Compound 18

LK6-A (60 mg, 0.19 mmol) was dissolved in dimethyl sulfoxide (3 ml), and 2-acetamido-2-deoxy-1-thio-β-D-glucopyranose-3,4,6-triacetate (80.6 mg, 0.22 mmol) was added thereto, followed by stirring at room temperature for 12 hours. After water (200 ml) was added to the reaction mixture, the product was extracted with chloroform (200 ml). The product was purified by silica gel column chromatography with chloroform/methanol (98:2), whereby Compound 18 (12 mg, 9.2%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 1.79 (s, 3H), 1.85 (s, 3H), 1.94 (s, 3H), 1.99 (s, 3H), 2.34 (s, 3H), 3.95 (s, 3H), 3.9-4.0 (m, 1H), 4.05 (d, J=9.8 Hz, 1H), 4.09 (dd, J=12.5, 2.2 Hz, 1H), 4.23 (dd, J=12.5, 4.6 Hz, 1H), 4.96 (t, J=9.8 Hz, 1H), 5.21 (t, J=9.8 Hz, 1H), 5.65 (d, J=10.5 Hz, 1H), 7.64 (d, J=12.5 Hz, 1H), 7.89 (d, J=12.5 Hz, 1H), 8.15 (s, 1H), 8.24 (br s, 2H), 8.61 (s, 1H), 10.2 (s, 1H)

FABMS m/z 672 (M+H)⁺ C₃₀H₃₃N₅O₁₁ S=671.

EXAMPLE 18 Compound 19

LK6-A (60 mg, 0.19 mmol) was dissolved in dimethyl sulfoxide (4 ml), and 1-thio-β-D-glucose-2,3,4,6-tetraacetate (84.6 mg, 0.23 mmol) was added thereto, followed by stirring at room temperature for 12 hours. After water (200 ml) was added to the reaction mixture, the product was extracted with chloroform (200 ml). The product was purified by silica gel column chromatography with chloroform/methanol (99:1), whereby Compound 19 (8.0 mg, 6.2%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 1.91 (s, 3H), 1.94 (s, 3H), 1.99 (s, 3H), 2.02 (s, 3H), 2.35 (s, 3H), 3.94 (s, 3H), 4.1-4.3 (m, 3H), 4.9-5.1 (m, 2H), 5.40 (t, J=9.5 Hz, 1H), 5.70 (d, J=10.3 Hz, 1H), 7.63 (d, J=12.5 Hz, 1H), 7.89 (d, J=12.5 Hz, 1H), 8.15 (s, 1H), 8.3-8.4 (m, 2H), 8.63 (s, 1H), 10.2 (s, 1H)

FABMS m/z 673 (M+H)⁺ C₃₀H₃₂N₄O₁₂S=672.

EXAMPLE 19 Compound 20

LK6-A (29.4 mg, 0.09 mmol) was dissolved in dimethyl sulfoxide (6 ml), and ethyl mercaptan (0.050 ml) was added thereto, followed by stirring at room temperature for 20 hours. To the reaction mixture was added water, and the resulting mixture was extracted with chloroform. The organic layer was washed twice with water and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol (49:1), whereby Compound 20 (23.1 mg, 66%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 1.41 (t, J=7.4 Hz, 3H), 2.31 (s, 3H), 3.39 (q, J=7.4 Hz, 2H), 3.93 (s, 3H), 7.60 (d, J=12.5 Hz, 1H), 7.79 (br s, 2H), 7.87 (d, J=12.5 Hz, 1H), 8.12 (s, 1H), 8.40 (s, 1H), 10.1 (s, 1H)

FABMS m/z 371 (M+H)⁺ C₁₈H₁₈N₄O₃S=370.

EXAMPLE 20 Compound 21

LK6-A (47.6 mg, 0.15 mmol) was dissolved in dimethyl sulfoxide (10 ml), and benzyl mercaptan (0.10 ml) was added thereto, followed by stirring at room temperature for 48 hours. The reaction mixture was diluted with chloroform, and the resulting diluted solution was passed through a silica gel column for adsorption, followed by elution with chloroform/methanol (9:1). After the eluate was concentrated under reduced pressure, chloroform was added to the residue. The resulting mixture was washed three times with water and the organic layer was dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol (24:1), whereby Compound 21 (25.9 mg, 39%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 2.33 (s, 3H), 3.94 (s, 3H), 4.68 (s, 2H), 7.24 (t, J=7.3 Hz, 1H), 7.31 (t, J=7.3 Hz, 2H), 7.52 (d, J=7.3 Hz, 2H), 7.61 (d, J=12.5 Hz, 1H), 7.87 (d, J=12.5 Hz, 1H), 7.90 (br s, 2H), 8.14 (s, 1H), 8.40 (s, 1H), 10.1 (s, 1H)

FABMS m/z 433 (M+H)⁺ C₂₃H₂₀N₄O₃S=432.

EXAMPLE 21 Compound 22

LK6-A (62 mg, 0.20 mmol) was dissolved in dimethylformamide (6 ml), and N-chlorosuccinimide (40 mg, 0.30 mmol) was added thereto, followed by stirring at room temperature for 2 hours. To the reaction mixture was added water, and the resulting mixture was extracted with ethyl acetate. The organic layer was washed with a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by preparative thin layer chromatography with chloroform/methanol (9:1), followed by trituration with diisopropyl ether, whereby Compound 22 (8.2 mg, 12%) was obtained.

¹H NMR (500 MHz, DMSO-d₆) δ 2.35 (s, 3H), 3.95 (s, 3H), 7.63 (d, J=12.5 Hz, 1H), 7.90 (d, J=12.5 Hz, 1H), 8.16 (s, 1H), 8.49 (s, 1H), 10.2 (s, 1H)

FABMS m/z 345 (M+H)⁺ C₁₆H₁₃ ³⁵ClN₄O₃=344.

EXAMPLE 22 Compound 23

The same procedure as in Example 21 was repeated, except that N-bromosuccinimide was used in place of N-chlorosuccinimide, whereby Compound 23 (11 mg, 14%) was obtained.

¹H NMR (500 MHz, DMSO-d₆) δ 2.35 (s, 3H), 3.95 (s, 3H), 7.63 (d, J=12.5 Hz, 1H), 7.90 (d, J=12.5 Hz, 1H), 8.15 (s, 1H), 8.40 (s, 1H), 10.2 (s, 1H)

FABMS m/z 391, 389 (M+H)⁺ C₁₆H₁₃ BrN₄O₃=388.

EXAMPLE 23 Compound 24

The same procedure as in Example 21 was repeated, except that N-iodosuccinimide was used in place of N-chlorosuccinimide, whereby Compound 24 (11 mg, 13%) was obtained.

¹H NMR (500 MHz, DMSO-d₆) δ 2.34 (s, 3H), 3.95 (s, 3H), 7.63 (d, J=12.5 Hz, 1H), 7.90 (d, J=12.5 Hz, 1H), 8.14 (s, 1H), 8.22 (s, 1H), 10.2 (s, 1H)

FABMS m/z 437 (M+H)⁺ C₁₆H₁₃ IN₄O₃=436

EXAMPLE 24 Compound 25

LK6-A (1.55 g, 5.00 mmol) was suspended in chloroform (200 ml), and methanol (40 ml) and potassium carbonate (2.07 g, 15.0 mmol) were added thereto, followed by stirring at room temperature for 24 hours. To the reaction mixture was added water, and the resulting mixture was extracted with chloroform/methanol (9: 1). After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol (30:1), whereby Compound 25 (1.20 g, 70%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 2.33 (s, 3H), 3.32 (s, 6H), 3.78 (d, J=5.7 Hz, 2H), 5.05 (t, J=5.7 Hz, 1H), 8.21 (s, 1H), 8.28 (br s, 1H), 8.37 (s, 1H), 8.52 (s, 1H)

FABMS m/z 343 (M+H)⁺ C₁₇H₁₈N₄O₄=342.

EXAMPLE 25 Compound 26

LK6-A (1.00 g, 3.23 mol) was suspended in methanol (90 ml), and a 1 N aqueous solution of sodium hydroxide (20 ml) was added thereto, followed by stirring at room temperature for 2.5 hours. To the reaction mixture was added water, and the resulting mixture was extracted with chloroform. After the solvent-was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol (9:1), whereby Compound 26 (359 mg, 37%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 3.30 (s, 6H), 3.68 (d, J=5.9 Hz, 2H), 5.03 (t, J=5.9 Hz, 1H), 5.94 (s, 1H), 7.10 (br s, 2H), 7.75 (br s, 2H), 8.08 (s, 1H), 8.44 (s, 1H)

FABMS m/z 301 (M+H)⁺ C₁₅H₁₆N₄O₃=300.

EXAMPLE 26 Compound 27

Compound 26 (80 mg, 0.27 mmol) was dissolved in dimethyl sulfoxide (15 ml), and Molecular Sieves 4A (300 mg) was added thereto, followed by stirring at 90-100° C. for 43 hours. To the reaction mixture was added water, and the resulting mixture was extracted with ethyl acetate (400 ml). After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol (9:1), followed by trituration with isopropyl ether, whereby Compound 27 (34 mg, 47%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ3.90 (s, 3H), 5.93 (s, 1H), 7.18 (br s, 2H), 7.53 (d, J=12.7 Hz, 1H), 7.70 (br s, 2H), 7.82 (d, J=12.7 Hz, 1H), 8.08 (s, 1H), 8.54 (s, 1H)

FABMS m/z 269 (M+H)⁺ C₁₄H₁₂N₄O₂=268.

EXAMPLE 27 Compound 28

Compound 25 (164 mg, 0.48 mmol) was dissolved in chloroform/methanol (9:1, 20 ml), and sodium borohydride (36 mg, 0.96 mmol) was added thereto under ice-cooling, followed by stirring at room temperature for 2 hours. To the reaction mixture was added water, and the resulting mixture was extracted twice with chloroform/methanol (9:1). After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol (19:1-14:1), followed by trituration with isopropyl ether, whereby Compound 28 (17 mg, 10%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 1.90 (ddd, J=13.7, 9.5, 3.7 Hz, 1H), 2.14 (ddd, J=13.7, 7.6, 3.7 Hz, 1H), 2.30 (s, 3H), 3.22 (s, 3H), 3.32 (s, 3H), 4.66 (dd, J=7.6, 3.7 Hz, 1H), 4.97 (ddd, J=9.5, 6.1, 3.7 Hz, 1H), 5.58 (d, J=6.4 Hz, 1H),7.66 (br s, 2H), 7.96 (s, 1H), 8.05 (s, 1H), 8.25 (s, 1H), 9.94 (s, 1H)

FABMS m/z 345 (M+H)⁺ C₁₇H₂₀N₄O₄=344.

EXAMPLE 28 Compound 29

Compound 26 (50 mg, 0.17 mmol) was dissolved in chloroform/methanol (9:1, 7 ml), and sodium borohydride (19 mg, 0.50 mmol) was added thereto under ice-cooling, followed by stirring at room temperature for 30 minutes. To the reaction mixture was added water, and the resulting mixture was extracted twice with ethyl acetate. After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol (9:1), followed by trituration with isopropyl ether, whereby Compound 29 (27 mg, 53%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 1.87 (ddd, J=13.4, 9.5, 3.9 Hz, 1H), 2.14 (ddd, J=13.4, 7.8, 3.9 Hz, 1H), 3.22 (s, 6H), 4.62 (dd, J=7.8, 3.9 Hz, 1H), 4.90 (ddd, J=9.3, 5.4, 3.9 Hz, 1H), 5.41 (d, J=5.4 Hz, 1H), 5.88 (s, 1H), 6.71 (br s, 2H), 7.24 (br s, 2H), 7.88 (s, 1H), 7.94 (s, 1H)

FABMS m/z 303 (M+H)⁺ C₁₅H₁₈N₄O₃ =302.

EXAMPLE 29 Compound 30

LK6-A (155 mg, 0.500 mmol) was dissolved in chloroform/methanol (9:1, 20 ml), and sodium borohydride (38 mg, 1.0 mmol) was added thereto under ice-cooling, followed by stirring at room temperature for 2 hours. To the reaction mixture was added water, and the resulting mixture was extracted twice with chloroform/methanol (9:1). After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol (14:1-9:1), followed by trituration with isopropyl ether, whereby Compound 30 (18 mg, 11%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 1.8-2.0 (m, 1H), 2.1-2.2 (m, 1H), 2.30 (s, 3H), 3.24 (s, 3H), 3.4-3.6 (m, 2H), 4.9-5.1 (m, 1H), 5.53 (d, J=6.1 Hz, 1H), 7.65 (br, 2H), 7.96 (s, 1H), 8.06 (s, 1H), 8.25 (s, 1H), 9.95 (br, 1H)

FABMS m/z 315 (M+H)⁺ C₁₆H₁₈N₄O₃=314.

EXAMPLE 30 Compounds 31 and 32

LK6-A (93 mg, 0.30 mmol) was suspended in chloroform (9 ml), and ethylene glycol (1.5 ml) and potassium carbonate (124 mg, 0.90 ml) were added thereto, followed by stirring at room temperature for 42 hours. To the reaction mixture was added water, and the resulting mixture was extracted with chloroform. The organic layer was washed once with water. After the solvent was evaporated under reduced pressure, the residue was purified by preparative thin layer chromatography with chloroform/methanol (6:1), followed by trituration with isopropyl ether, whereby Compound 31 (6.3 mg, 6.2%) and Compound 32 (8.4 mg, 9.4%) were obtained.

Compound 31: ¹H NMR(400 MHz, DMSO-d₆) δ 2.34 (s, 3H), 3.8-3.9 (m, 2H), 3.83 (d, J=5.4 Hz, 2H), 3.9-4.0 (m, 2H), 5.45 (t, J=5.4 Hz, 1H), 8.14 (s, 1H), 8.29 (br s, 2H), 8.37 (s, 1H1), 8.51 (s, 1H), 10.0 (s, 1H)

FABMS m/z 341 (M+H)⁺ C₁₇H₁₆N₄O₄=340.

Compound 32: ¹H NMR (400 MHz, DMSO-d₆) δ 3.70 (d, J=5.4 Hz, 2H), 3.7-3.9 (m, 2H), 3.9-4.0 (m, 2H), 5.46 (t, J=5.4 Hz, 1H), 5.93 (s, 1H), 7.13 (br s, 2H), 7.77 (br s, 2H), 8.09 (s, 1H), 8.44 (s, 1H)

FABMS m/z 299 (M+H)⁺ C₁₅H₁₄N₄O₃=298.

EXAMPLE 31 Compounds 33 and 34

The same procedure as in Example 30 was repeated, except that propylene glycol was used in place of ethylene glycol, whereby Compound 33 (17 mg, 16%) and Compound 34 (15 mg, 16%) were obtained.

Compound 33: ¹H NMR (400 MHz, DMSO-d₆) δ 1.36 (m, 1H), 1.90 (m, 1H), 2.35 (s, 3H), 3.7-3.8 (m, 2H), 3.75 (d, J=5.4 Hz, 2H), 3.9-4.1 (m, 2H), 5.24 (t, J=5.4 Hz, 1H), 8.13 (s, 1H), 8.28 (br s, 2H), 8.37 (s, 1H), 8.50 (s, 1H), 10.0 (s, 1H)

FABMS m/z 355 (M+H)⁺ C₁₈H₁₈N₄O₄=354.

Compound 34: ¹H NMR (400 MHz, DMSO-d₆) δ 1.34 (m, 1H), 1.88 (m, 1H), 3.63 (d, J=5.4 Hz, 2H), 3.7-3.8 (m, 2H), 3.9-4.0 (m, 2H), 5.21 (t, J=5.4 Hz, 1H), 5.93 (s, 1H), 7.11 (br s, 2H), 7.76 (br s, 2H), 8.08 (s, 1H), 8.43 (s, 1H)

FABMS m/z 313 (M+H)⁺ C₁₆H₁₆N₄O₃=312.

EXAMPLE 32 Compound 35

LK6-A (50 mg, 0.16 mmol) was dissolved in chloroform/methanol (9:1, 7 ml), and triethylamine (0.067 ml, 0.48 mmol) and methyl chloroformate (0.025 ml, 0.32 mmol) were added thereto, followed by stirring at room temperature for 45 minutes. To the reaction mixture was added water, and the resulting mixture was extracted with chloroform/methanol (9:1). After the solvent was evaporated under reduced pressure, the residue was triturated with isopropyl ether, whereby Compound 35 (45 mg, 76%) was obtained.

¹H NMR (400 MHz, CDCl₃+CD₃CO₂D) δ 2.37 (s, 3H), 3.90 (s, 3H), 3.92 (s, 3H), 7.10 (d, J=12.5 Hz, 1H), 7.90 (d, J=1.0 Hz, 1H), 7.93 (d, J=12.5 Hz, 1H), 8.18 (s, 1H), 8.38 (s, 1H)

FABMS m/z 369 (M+H)⁺ C₁₈H₁₆N₄O₅=368.

EXAMPLE 33 Compound 36

The same procedure as in Example 32 was repeated, except that ethyl chloroformate was used in place of methyl chloroformate, whereby Compound 36 (64%) was obtained.

¹H NMR (400 MHz, CDCl₃+CD₃CO₂D) δ 1.36 (t, J=7.1 Hz, 3H), 2.37 (s, 3H), 3.92 (s, 3H), 4.3-4.4 (m, 2H), 7.11 (d, J=12.5 Hz, 1H), 7.94 (d, J=12.5 Hz, 1H), 7.94 (d, J=1.0 Hz, 1H), 8.17 (d, J=0.7 Hz, 1H), 8.38 (5, 1H)

FABMS m/z 383 (M+H)⁺ C₁₉H₁₈N₄O₅=382.

EXAMPLE 34 Compound 37

The same procedure as in Example 32 was repeated, except that n-propyl chloroformate was used in place of methyl chloroformate, whereby Compound 37 (85%) was obtained.

¹H NMR (400 MHz, CDCl₃+CD₃CO₂D) δ 1.01 (t, J=7.5 Hz, 3H), 1.7-1.8 (m, 2H), 2.37 (s, 3H), 3.92 (s, 3H), 4.1-4.3 (m, 2H), 7.11 (d, J=12.5 Hz, 1H), 7.93 (d, J=12.5 Hz, 1H), 7.94 (d, J=1.0 Hz, 1H), 8.18 (s, 1H), 8.38 (s, 1H)

FABMS m/z 313 (M+H)⁺ C₂₀H₂₀N₄O₅=312.

EXAMPLE 35 Compound 38

The same procedure as in Example 32 was repeated, except that n-butyl chloroformate was used in place of methyl chloroformate, whereby Compound 38 (56%) was obtained.

¹H NMR (400 MHz, CDCl₃+CD₃ CO₂D) δ 0.93 (t, J=7.3 Hz, 3H), 1.3-1.5 (m, 2H), 1.6-1.8 (m, 2H), 2.35 (s, 3H), 3.91 (s, 3H), 4.12 (t, J=6.7 Hz, 2H), 7.09 (d, J=12.0 Hz, 1H), 7.91 (d, J=1.0 Hz, 1H), 7.92 (d, J=12.2 Hz, 1H), 8.17 (d, J=1.0 Hz, 1H), 8.36 (s, 1H)

FABMS m/z 411 (M+H)⁺ C₂₁H₂₂N₄O₅=410.

EXAMPLE 36 Compound 39

The same procedure as in Example 32 was repeated, except that n-octyl chloroformate was used in place of methyl chloroformate, whereby Compound 39 (79%) was obtained.

¹H NMR (400 MHz, CDCl₃+CD₃CO₂D) δ 0.8-1.8 (m, 15H), 2.36 (s, 3H), 3.92 (s, 3H), 4.2-4.4 (m, 2H), 7.11 (d, J=12.5 Hz, 1H), 7.93 (d, J=12.7 Hz, 1H), 7.93 (s, 1H), 8.18 (s, 1H), 8.37 (s, 1H)

FABMS m/z 467 (M+H)⁺ C₂₅H₃₀N₄O₄=466.

EXAMPLE 37 Compound 40

The same procedure as in Example 32 was repeated, except that benzyl chloroformate was used in place of methyl chloroformate, whereby Compound 40 (80%) was obtained.

¹H NMR (400 MHz, CDCl₃+CD₃CO₂D) δ 2.36 (s, 3H), 3.91 (s, 3H), 5.17 (s, 2H), 7.10 (d, J=12.5 Hz, 1H), 7.3-7.5 (m, 5H), 7.92 (d, J=12.5 Hz, 1H), 7.94 (d, J=0.7 Hz, 1H), 8.16 (s, 1H), 8.37 (s, 1H)

FABMS m/z 445 (M+H)⁺ C₂₄H₂₀N₄O₅=444.

EXAMPLE 38 Compound 41

Compound 25 (97 mg, 0.28 mmol) was dissolved in dimethylformamide (5 ml), and sodium hydride (57 mg, 1.4 mmol) and iodomethane (0.088 ml, 1.4 mmol) were added thereto under ice-cooling, followed by stirring at room temperature for one hour. To the reaction mixture was added water, and the resulting mixture was extracted with ethyl acetate. After the solvent was evaporated under reduced pressure, the residue was purified by preparative thin layer chromatography with chloroform/methanol (9:1), followed by trituration with isopropyl ether, whereby Compound 41 (26 mg, 23%) was obtained.

¹H NMR (400 MHz, CDCl₃) δ 1.27 (d, J=7.1 Hz, 3H), 2.00 (s, 3H), 3.30 (s, 3H), 3.39 (s, 3H), 3.51 (s, 3H), 3.68 (br s, 6H), 4.67 (quintet, J=7.1 Hz, 1H), 4.84 (d, J=7.8 Hz, 1H), 7.17 (s, 1H), 8.54 (s, 1H), 8.64 (s, 1H)

FABMS m/z 399 (M+H)⁺ C₂₁H₂₆N₄O₄=398.

EXAMPLE 39 Compounds 42 and 43

Compound 26 (60 mg, 0.20 mmol) was dissolved in dimethylformamide (4 ml) in an atmosphere of argon, and sodium hydride (48 mg, 1.2 mmol) and iodomethane (0.075 ml, 1.2 mmol) were added thereto under ice-cooling, followed by stirring at room temperature for 15 minutes. To the reaction mixture was added water, and the resulting mixture was extracted with ethyl acetate. After the solvent was evaporated under reduced pressure, the residue was purified by preparative thin layer chromatography-with chloroform/methanol (9:1). Then, the obtained two fractions were triturated with isopropyl ether, whereby Compound 42 (32 mg, 35%) and Compound 43 (5.7 mg, 7.7%) were obtained.

Compound 42: ¹H NMR (400 MHz, CDCl₃) δ 1.28 (d, J=7.1 Hz, 3H), 3.33 (s, 3H), 3.43 (s, 3H), 3.62 (s, 6H), 3.65 (br s, 6H), 4.70 (quintet, J=7.1 Hz, 1H), 4.82 (d, J=8.3 Hz, 1H), 5.72 (s, 1H), 8.31 (s, 1H), 8.64 (s, 1H)

FABMS m/z 371 (M+H)⁺ C₂₀H₂₆N₄O₃=370.

Compound 43: ¹H NMR (400 MHz, CDCl₃) δ 3.62 (s, 6H), 3.65 (br s, 6H), 3.85 (s, 3H), 5.77 (s, 1H), 7.27 (d, J=13.2 Hz, 1H), 7.93 (d, J=12.7 Hz, 1H), 8.32 (s, 1H), 8.72 (s, 1H)

FABMS m/z 325 (M+H)⁺ C₁₈H₂₀N₄O₂=324.

EXAMPLE 40 Compound 44

Compound 25 (900 mg, 2.63 mmol) was dissolved in chloroform/methanol (9:1, 100 ml), and triethylamine (0.73 ml, 5.3 mmol) and tetrabutylammonium tribromide (2.04 g, 4.21 mmol) were added thereto, followed by stirring at room temperature for 20 minutes. To the reaction mixture was added water, and the resulting mixture was extracted twice with chloroform/methanol (9:1). The organic layer was washed with a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol (30:1), whereby Compound 44 (1.02 g, 92%) was obtained.

¹H NMR (500 MHz, DMSO-d₆) δ 2.34 (s, 3H), 3.32 (s, 6H), 3.79 (d, J=5.6 Hz, 2H), 5.04 (t, J=5.6 Hz, 1H), 8.13 (s, 1H), 8.28 (s, 1H), 10.1 (br s, 1H)

FABMS m/z 423, 421 (M+H)⁺ C₁₇H₁₇ ⁷⁹ BrN₄O₄=420.

EXAMPLE 41 Compound 45

Compound 44 (100 mg, 0.238 mmol) was dissolved in dimethylformamide (10 ml), and diisopropylethylamine (0.21 ml, 1.2 mmol) and dimethylamine hydrochloride (98 mg, 1.2 mmol) were added thereto, followed by stirring at 70° C. for 2.5 hours. To the reaction mixture was added water, and the resulting mixture was extracted twice with ethyl acetate. The organic layer was washed with a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol (30:1), whereby Compound 45 (27 mg, 29%) was obtained.

¹H NMR (400 MHz, CDCl₃) δ 2.27 (s, 3H), 3.32 (s, 6H), 3.38 (s, 6H), 3.76 (d, J=5.6 Hz, 2H), 5.07 (t, J=5.6 Hz, 1H), 6.79 (br s, 2H), 8.05 (s, 1H), 8.44 (s, 1H), 9.82 (s, 1H)

FABMS m/z 386 (M+H)⁺ C₁₉H₂₃N₅O₄=385.

EXAMPLE 42 Compound 46

Compound 45 (46 mg, 0.12 mmol) was dissolved in dimethyl sulfoxide (10 ml), and Molecular Sieves 4A (200 mg) was added thereto, followed by stirring at 90° C. for 40 hours. To the reaction mixture was added chloroform (200 ml), and the resulting mixture was passed through a silica gel column for adsorption, followed by elution with chloroform/methanol/triethylamine (190:10:3). The eluate was triturated with isopropyl ether, whereby Compound 46 (14 mg, 33%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 2.30 (s, 3H), 3.45 (br s, 6H), 3.95 (s, 3H), 6.95 (br s, 2H), 7.60 (d, J=12.7 Hz, 1H), 7.89 (d, J=12.4 Hz, 1H), 8.14 (s, 1H), 8.60 (s, 1H), 10.0 (br s, 1H)

FABMS m/z 354 (M+H)⁺ C₁₈H₁₉N₅O₃=353.

EXAMPLE 43 Compound 47

Compound 44 (150 mg, 0.356 mmol) was dissolved in dimethylformamide (10 ml), and 1-methylpiperazine (0.20 ml, 1.8 mmol) was added thereto, followed by stirring at 70° C. for 6 hours. To the reaction mixture was added water, and the resulting mixture was extracted twice with ethyl acetate. The organic layer was washed with a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol (9:1), followed by trituration with isopropyl ether, whereby Compound 47 (88 mg, 56%) was obtained.

¹H NMR (400 MHz, CDCl₃) δ 2.35 (s, 3H), 2.39 (s, 3H), 2.62 (t, J=5.1 Hz, 4H), 3.46 (s, 6H), 3.73 (d, J=5.6 Hz, 2H), 3.94 (t, J=5.1 Hz, 4H), 5.14 (br s, 2H), 5.15 (t, J=5.6 Hz, 1H), 8.15 (s, 1H), 8.56 (s, 1H), 8.94 (br s, 1H)

FABMS m/z 441 (M+H)⁺ C₂₂H₂₈N₆O₄=440.

EXAMPLE 44 Compound 48

The same procedure as in Example 42 was repeated, except that Compound 47 (60 mg, 0.14 mmol) was used in place of Compound 45, whereby Compound 48 (31 mg, 54%) was obtained.

¹H NMR (400 MHz, CDCl₃) δ 2.36 (s, 3H), 2.39 (s, 3H), 2.62 (t, J=5.1 Hz, 4H), 3.94 (s, 3H), 3.95 (t, J=5.1 Hz, 4H), 5.06 (br s, 2H), 7.23 (d, J=12.5 Hz, 1H), 7.94 (d, J=12.5 Hz, 1H), 8.14 (s, 1H), 8.64 (s, 1H), 8.95 (br s, 1H)

FABMS m/z 409 (M+H)⁺ C₂₁H₂₄N₆O₃=408.

EXAMPLE 45 Compound 49

The same procedure as in Example 43 was repeated, except that morpholine (0.16 ml, 1.8 mmol) was used in place of 1-methylpiperazine, whereby Compound 49 (93 mg, 61%) was obtained from Compound 44 (150 mg, 0.356 mmol).

¹H NMR (400 MHz, CDCl₃) δ 2.36 (s, 3H), 3.46 (s, 6H), 3.73 (d, J=5.6 Hz, 2H), 3.8-3.9 (m, 8H), 5.13 (br s, 2H), 5.15 (t, J=5.6 Hz, 1H), 8.16 (s, 1H), 8.54 (s, 1H), 8.94 (br s, 1H)

FABMS m/z 428 (M+H)⁺ C₂₁H₂₅N₅O₅=427.

EXAMPLE 46 Compound 50

The same procedure as in Example 42 was repeated, except that Compound 49 (60 mg, 0.14mmol) was used in place of Compound 45, whereby Compound 50 (42 mg, 76%) was obtained.

¹H NMR (400 MHz, CDCl₃) δ 2.36 (s, 3H), 2.61 (s, 2H), 3.91 (s, 6H), 3.94 (s, 3H), 5.07 (br s, 2H), 7.22 (d, J=12.5 Hz, 1H), 7.94 (d, J=12.5 Hz, 1H), 8.15 (s, 1H), 8.62 (s, 1H), 8.96 (br s, 1H)

FABMS m/z 396 (M+H)⁺ C₂₀H₂₁N₅O₄=395.

EXAMPLE 47 Compound 51

The same procedure as in Example 43 was repeated, except that sodium azide (154 mg, 2.38 mmol) was used in place of 1-methylpiperazine, whereby Compound 51 (104 mg, 76%) was obtained from Compound 44 (200 mg, 0.475 mmol).

¹H NMR (400 MHz, DMSO-d₆) δ 2.36 (s, 3H), 3.34 (s, 6H), 3.83 (d, J=5.6 Hz, 2H), 5.07 (t, J=5.6 Hz, 1H), 7.98 (br s, 2H), 8.40 (s, 1H), 8.78 (s, 1H), 10.2 (br s, 1H)

FABMS m/z 384 (M+H)⁺ C₁₇H₁₇N₇O₄=383.

EXAMPLE 48 Compound 52

The reaction was carried out in a manner similar to that in Example 42, except that Compound 51 (60 mg, 0.14 mmol) was used in place of Compound 45. The reaction mixture was filtered, followed by addition of water and extraction with ethyl acetate. The organic layer was washed with water and a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was triturated with isopropyl ether, whereby Compound 52 (12 mg, 21%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 2.37 (s, 3H), 3.97 (s, 3H), 7.62 (d, J=12.7 Hz, 1H), 7.92 (br s, 2H), 7.94 (d, J=12.5 Hz, 1H), 8.42 (s, 1H), 8.85 (s, 1H), 10.3 (br s, 1H)

FABMS m/z 352 (M+H)⁺ C₁₆H₁₃N₇O₃=351.

EXAMPLE 49 Compound 53

Compound 25 (200 mg, 0.585 mmol) was dissolved in dimethyl sulfoxide (10 ml), and benzylamine (0.64 ml, 59 mmol) was added thereto, followed by stirring at room temperature for 4 days. To the reaction mixture was added water, and the resulting mixture was extracted with ethyl acetate. The organic layer was washed with water and a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol (9:1), whereby Compound 53 (214 mg, 81%) was obtained.

¹H NMR (300 MHz, CDCl₃) δ 2.26 (s, 3H), 3.31 (s, 6H), 3.74 (d, J=5.9 Hz, 2H), 4.75 (d, J=5.4 Hz, 2H), 5.06 (t, J=5.9 Hz, 1H), 6.62 (br s, 2H), 7.26 (t, J=7.3 Hz, 1H), 7.35 (t, J=7.5 Hz, 2H), 7.44 (d, J=7.6 Hz, 2H), 7.99 (s, 1H), 8.37 (br s, 1H), 8.66 (s, 1H), 9.78 (s, 1H)

FABMS m/z 448 (M+H)⁺ C₂₄ H₂₅N₅O₄=447.

EXAMPLE 50 Compound 54

The reaction was carried out in a manner similar to that in Example 42, except that Compound 53 (60 mg, 0.14 mmol) was used in place of Compound 45. The reaction mixture was filtered, followed by addition of water and extraction with ethyl acetate. The organic layer was washed with water and a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by preparative thin layer chromatography with chloroform/methanol (9:1), followed by trituration with isopropyl ether, whereby Compound 54 (6.1 mg, 33%) was obtained.

¹H NMR (300 MHz, DMSO-d₆) δ 2.28 (s, 3H), 3.93 (s, 3H), 4.75 (br s, 2H), 6.57 (br s, 2H), 7.27 (t, J=7.6 Hz, 1H), 7.35 (t, J=7.6 Hz, 2H), 7.45 (d, J=7.6 Hz, 2H), 7.61 (d, J=12.7 Hz, 1H), 7.87 (d, J=12.7 Hz, 1H), 8.03 (s, 1H), 8.42 (br s, 1H), 8.78 (s, 1H), 9.92 (s, 1H)

FABMS m/z 416 (M+H)⁺ C₂₃H₂₁N₅O₃=415.

EXAMPLE 51 Compound 55

Compound 25 (50 mg, 0.15 mmol) was dissolved in dimethyl sulfoxide (3 ml), and piperidine (0.14 ml, 1.5 mmol) was added thereto, followed by stirring at room temperature for 20 hours. To the reaction mixture was added water, and the resulting mixture was extracted with ethyl acetate. The organic layer was washed with water and a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol (50:1), whereby Compound 55 (53 mg, 83%) was obtained.

¹H NMR (300 MHz, CDCl₃) δ 1.79 (br s, 6H), 2.36 (s, 3H), 3.46 (s, 6H), 3.73 (d, J=5.7 Hz, 2H), 3.96 (br s, 4H), 5.15 (t, J=5.7 Hz, 1H), 8.18 (s, 1H), 8.61 (br s, 1H), 8.92 (s, 1H)

FABMS m/z 426 (M+H)⁺ C₂₂H₂₇N₅O₄=425.

EXAMPLE 52 Compound 56

The same procedure as in Example 50 was repeated, except that Compound 55 (47 mg, 0.11 mmol) was used in place of Compound 53, whereby Compound 56 (21 mg, 49%) was obtained.

¹H NMR (300 MHz, DMSO-d₆) δ 1.69 (br s, 6H), 2.29 (s, 3H), 3.84 (br s, 2H), 3.94 (s, 3H), 6.79 (br s, 2H), 7.62 (d, J=12.5 Hz, 1H), 7.88 (d, J=12.5 Hz, 1H), 8.08 (s, 1H), 8.57 (br s, 1H), 9.98 (s, 1H)

FABMS m/z 416 (M+H)⁺ C₂₃H₂₁N₅O₃=415.

EXAMPLE 53 Compound 57

Compound 25 (50 mg, 0.15 mmol) was dissolved in dimethyl sulfoxide (3 ml), and aniline (0.15 ml, 1.5 mmol) was added thereto, followed by stirring at room temperature for 20 hours. To the reaction mixture was added water, and the resulting mixture was extracted with ethyl acetate. The organic layer was washed with water and a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was triturated with isopropyl ether, whereby Compound 57 (44 mg, 68%) was obtained.

¹H NMR (300 MHz, DMSO-d₆) δ 2.29 (s, 3H), 3.3-3 (s, 6H), 3.78 (d, J=5.9 Hz, 2H), 5.08 (t, J=5.9 Hz, 1H), 6.97 (t, J=7.5 Hz, 1H), 7.06 (br s, 2H), 7.35 (t, J=7.5 Hz, 2H), 8.07 (s, 1H), 8.16 (d, J=8.1 Hz, 2H), 8.90 (s, 1H), 9.90 (s, 1H), 10.2 (s, 1H)

FABMS m/z 434 (M+H)⁺ C₂₃H₂₃N₅O₄=433.

EXAMPLE 54 Compound 58

The same procedure as in Example 50 was repeated, except that Compound 57 (32 mg, 0.074 mmol) was used in place of Compound 53, whereby Compound 58 (7.5 mg, 25%) was obtained.

¹H NMR (300 MHz, DMSO-d₆) δ 2.30 (s, 3H), 3.95 (s, 3H), 6.79 (t, J=7.3 Hz, 1H), 6.99 (br s, 2H), 7.35 (t, J=8.1 Hz, 2H), 7.66 (d, J=12.5 Hz, 1H), 7.91(d, J=12.5 Hz, 1H), 8.10 (s, 1H), 8.17 (d, J=8.1 Hz, 2H), 9.01 (s, 1H), 10.0 (s, 1H), 10.2 (s, 1H)

FABMS m/z 402 (M+H)⁺ C₂₂H₁₉N₅O₃=401.

EXAMPLE 55 Compound 59

Compound 25 (50 mg, 0.15 mmol) was dissolved in dimethyl sulfoxide (3 ml), and n-butylamine (0.15 ml, 1.5mmol)was added thereto, followed by stirring at room temperature for 20 hours. To the reaction mixture was added water, and the resulting mixture was extracted with ethyl acetate. The organic layer was washed with water and a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by preparative thin layer chromatography with chloroform/methanol (9:1), whereby Compound 59 (32 mg, 52%) was obtained.

¹H NMR (300 MHz, DMSO-d₆) δ 0.94 (t, J=7.5 Hz, 3H), 1.43 (sextet, J=7.5 Hz, 2H), 1.66 (quintet, J=7.4 Hz, 2H), 2.05 (s, 3H), 3.30 (s, 6H), 3.50 (br t, 2H), 3.74 (d, J=5.7 Hz, 2H), 5.06 (t, J=5.7 Hz, 1H), 6.65 (br s, 1H), 8.00 (s, 1H), 8.65 (s, 1H), 9.82 (s, 1H)

FABMS m/z 414 (M+H)⁺ C₂₁H₂₇N₅O₄=413.

EXAMPLE 56 Compound 60

The same procedure as in Example 50 was repeated, except that Compound 59 (27 mg, 0.065 mmol) was used in place of Compound 53, whereby Compound 60 (12 mg, 48%) was obtained.

₁H NMR (300 MHz, DMSO-d₆) δ 0.94 (t, J=7.2 Hz, 3H), 1.43 (sextet, J=7.2 Hz, 2H), 1.67 (quintet, J=7.2 Hz, 2H), 2.28 (s, 3H), 3.50 (t, J=7.2 Hz, 2H), 3.93 (s, 3H), 6.59 (br s, 2H), 7.61 (d, J=12.5 Hz, 1H), 7.88 (d, J=12.5 Hz, 1H), 8.04 (s, 1H), 8.77 (s, 1H), 9.94 (s, 1H)

FABMS m/z 382 (M+H)⁺ C₂₀H₂₃N₅O₃=381.

EXAMPLE 57 Compound 61

Compound 25 (50 mg, 0.15 mmol) was dissolved in dimethyl sulfoxide (3 ml), and propargylamine (0.20 ml, 3.0 mmol) was added thereto, followed by stirring at room temperature for 6 days. To the reaction mixture was added water, and the resulting mixture was extracted with ethyl acetate. The organic layer was washed with water and a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by preparative thin layer chromatography with chloroform/methanol (9:1), whereby Compound 61 (27 mg, 46%) was obtained.

¹H NMR (300 MHz, DMSO-d₆) δ 2.26 (s, 3H), 3.21 (t, J=2.6 Hz, 1H), 3.31 (s, 6H), 3.75 (d, J=5.9 Hz, 2H), 4.31 (dd, J=5.3, 2.6 Hz, 2H), 5.05 (t, J=5.8 Hz, 1H), 6.78 (br s, 2H), 8.00 (s, 1H), 8.26 (t, J=5.3 Hz, 1H), 8.62 (s, 1H), 9.82 (s, 1H)

FABMS m/z 396 (M+H)⁺ C₂₀H₂₁N₅O₄=395.

EXAMPLE 58 Compound 62

The same procedure as in Example 50 was repeated, except that Compound 61 (24 mg, 0.061 mmol) was used in place of Compound 53, whereby Compound 62 (3.5 mg, 16%) was obtained.

¹H NMR (300 MHz, DMSO-d₆) δ 2.28 (s, 3H), 3.21 (s, 1H), 3.93 (s, 3H), 4.31 (br s, 2H), 6.70 (br s, 2H), 7.61 (d, J=12.2 Hz, 1H), 7.87 (d, J=12.1 Hz, 1H), 8.04 (s, 1H), 8.27 (br s, 1H), 8.74 (s, 1H), 9.95 (s, 1H)

FABMS m/z 364 (M+H)⁺ C₁₉H₁₇N₅O₃=363.

EXAMPLE 59 Compound 63

Compound 25 (200 mg, 0.585 mmol) was dissolved in dimethyl sulfoxide (10 ml), and 4-methoxybenzylamine (0.76 ml, 59 mmol) was added thereto, followed by stirring at room temperature for 4 days. To the reaction mixture was added water, and the resulting mixture was extracted with ethyl acetate. The organic layer was washed with water and a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol (30:1), whereby Compound 63 (260 mg, 93%) was obtained.

¹H NMR (400 MHz, CDCl₃) δ 2.35 (s, 3H), 3.44 (s, 6H), 3.71 (d, J=5.6 Hz, 2H), 3.82 (s, 3H), 4.78 (s, 2H), 5.08 (br s, 2H), 5.13 (t, J=5.6 Hz, 1H), 6.91 (d, J=8.9 Hz, 2H), 7.37 (d, J=8.6 Hz, 1H), 8.16 (s, 1H), 8.40 (s, 1H), 8.87 (br s, 1H)

FABMS m/z 478 (M+H)⁺ C₂₅H₂₇N₅O₅=477.

EXAMPLE 60 Compound 64

Compound 63 (44 mg, 0.092 mmol) was dissolved indimethyl sulfoxide (7 ml), and Molecular Sieves 4A (200 mg) was added thereto, followed by stirring at 90° C. for 26 hours. To the reaction mixture was added chloroform (200 ml), and the resulting mixture was passed through a silica gel column for adsorption, followed by elution with chloroform/methanol (30:1). The eluate was purified by preparative thin layer chromatography with chloroform/methanol (9:1), followed by trituration with isopropyl ether, whereby Compound 64 (8.0 mg, 20%) was obtained.

¹H NMR (300 MHz, DMSO-d₆) δ 2.28 (s, 3H), 3.73 (s, 3H), 3.93 (s, 3H), 4.67 (br s, 2H), 6.58 (br s, 2H), 6.91 (d, J=8.8 Hz, 2H), 7.37 (d, J=8.8 Hz, 2H), 7.61 (d, J=12.7 Hz, 1H), 7.87 (d, J=12.7 Hz, 1H), 8.04 (s, 1H), 8.37 (br s, 1H), 8.77 (s, 1H), 9.93 (s, 1H)

FABMS m/z 446 (M+H)⁺ C₂₄H₂₃N₅O₄=445.

EXAMPLE 61 Compound 65

Compound 25 (50 mg, 0.15 mmol) was dissolved in dimethyl sulfoxide (3ml), and diethylamine (0.31 ml, 3.0mmol) was added thereto, followed by stirring at room temperature for 6 days. To the reaction mixture was added water, and the resulting mixture was extracted with ethyl acetate. The organic layer was washed with water and a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with toluene/ethyl acetate/methanol (5:10:1), whereby Compound 65 (24 mg, 39%) was obtained.

¹H NMR (300 MHz, DMSO-d₆) δ 1.29 (t, J=7.0 Hz, 6H), 2.27 (s, 3H), 3.32 (s, 6H), 3.7-3.9 (m, 4H), 3.76 (d, J=5.9 Hz, 2H), 5.06 (t, J=5.7 Hz, 1H), 6.72 (br s, 2H), 8.04 (s, 1H), 8.36 (s, 1H), 9.84 (s, 1H)

FABMS m/z 414 (M+H)⁺ C₂₁H₂₇N₅O₄=413.

EXAMPLE 62 Compound 66

Compound 65 (22 mg, 0.053 mmol) was dissolved indimethyl sulfoxide (5 ml), and Molecular Sieves 4A (120 mg) was added thereto, followed by stirring at 90° C. for 24 hours. To the reaction mixture was added water, and the resulting mixture was extracted with ethyl acetate. The organic layer was washed with water and a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by preparative thin layer chromatography with chloroform/methanol (9:1), whereby Compound 66 (27 mg, 46%) was obtained. ¹H NMR (400 MHz, DMSO-d₆) δ 1.30 (t, J=7.1 Hz, 6H), 2.28 (s, 3H), 3.81 (q, J=7.1 Hz, 4H), 3.94 (s, 3H), 6.62 (br s, 2H), 7.62 (d, J=12.5 Hz, 1H), 7.87 (d, J=12.7 Hz, 1H), 8.07 (s, 1H), 8.49 (s, 1H), 9.95 (s, 1H)

FABMS m/z 382 (M+H)⁺ C₂₀H₂₃N₅O₃ =381

EXAMPLE 63 Compound 67

Compound 25 (50 mg, 0.15 mmol) was dissolved in dimethyl sulfoxide (3 ml), and pyrrolidine (0.13 ml, 1.5 mmol) was added thereto, followed by stirring at room temperature for 5.5 hours. To the reaction mixture was added water, and the resulting mixture was extracted with ethyl acetate. The organic layer was washed with water and a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was triturated with isopropyl ether, whereby Compound 67 (41 mg, 67%) was obtained.

¹H NMR (300 MHz, DMSO-d₆) δ 2.0-2.1 (m, 4H), 2.27 (s, 3H), 3.32 (s, 6H), 3.7-3.9 (m, 4H), 3.76 (d, J=5.7 Hz, 2H), 5.07 (t, J=5.9 Hz, 1H), 6.77 (br s, 2H), 8.04 (s, 1H), 8.37 (s, 1H), 9.83 (s, 1H)

FABMS m/z 412 (M+H)⁺ C₂₁H₂₅N₅O₄=411.

EXAMPLE 64 Compound 68

The same procedure as in Example 50 was repeated, except that Compound 67 (32 mg, 0.078 mmol) was used in place of Compound 53, whereby Compound 68 (16 mg, 54%) was obtained.

¹H NMR (300 MHz, DMSO-d₆) δ 2.0-2.1 (m, 4H), 2.28 (s, 3H), 3.7-3.9 (m, 4H), 3.94 (s, 3H), 6.67 (br s, 2H), 7.62 (d, J=12.7 Hz, 1H), 7.88 (d, J=12.5 Hz, 1H), 8.08 (s, 1H), 8.49 (s, 1H), 9.94 (s, 1H)

FABMS m/z 380 (M+H)⁺ C₂₀H₂₁N₅O₃=379.

EXAMPLE 65 Compound 69

Compound 25 (50 mg, 0.15 mmol) was dissolved in dimethyl sulfoxide (3 ml), and 4-hydroxypiperidine (152 mg, 1.5 mmol) was added thereto, followed by stirring at room temperature for 5.5 hours. To the reaction mixture was added water, and the resulting mixture was extracted with ethyl acetate. The organic layer was washed with water and a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate, followed by evaporation of the solvent under reduced pressure, whereby Compound 69 (45 mg, 68%) was obtained.

¹H NMR (300 MHz, DMSO-d₆) δ 1.4-1.6 (m, 2H), 1.9-2.0 (m, 2H), 2.27 (s, 3H), 3.32 (s, 6H), 3.4-3.5 (m, 2H), 3.7-3.8 (m, 1H), 3.75 (d, J=5.9 Hz, 2H), 4.2-4.3 (m, 2H), 4.77 (d, J=4.4 Hz, 1H), 5.06 (t, J=5.9 Hz, 1H), 6.84 (br s, 2H), 8.03 (s, 1H), 8.46 (s, 1H), 9.82 (s, 1H)

FABMS m/z 442 (M+H)⁺ C₂₂H₂₇N₅O₅=441.

EXAMPLE 66 Compound 70

The same procedure as in Example 50 was repeated, except that Compound 69 (40 mg, 0.091 mmol) was used in place of Compound 53, whereby Compound 70 (20 mg, 54%) was obtained.

¹H NMR (300 MHz, DMSO-d₆) δ 1.4-1.6 (m, 2H), 1.8-2.0 (m, 2H), 2.29 (s, 3H), 3.4-3.6 (m, 2H), 3.7-3.9 (m, 1H), 3.94 (s, 3H), 4.2-4.3 (m, 2H), 4.79 (d, J=4.2 Hz, 1H), 6.79 (br s, 2H), 7.62 (d, J=12.7 Hz, 1H), 7.87 (d, J=12.7 Hz, 1H), 8.07 (s, 1H), 8.57 (s, 1H), 9.97 (s, 1H)

FABMS m/z 410 (M+H)⁺ C₂₁H₂₃N₅O₄=409.

EXAMPLE 67 Compound 71

Compound 25 (50 mg, 0.15 mmol) was dissolved in dimethyl sulfoxide (3 ml), and 2-methoxyethylamine (0.13 ml, 1.5 mmol) was added thereto, followed by stirring at room temperature for 6 days. To the reaction mixture was added water, and the resulting mixture was extracted with ethyl acetate. The organic layer was washed with water and a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol (19:1), whereby Compound 71 (36 mg, 58%) was obtained.

¹H NMR (300 MHz, DMSO-d₆) δ 2.26 (s, 3H), 3.31 (s, 6H), 3.32 (s, 3H), 3.6-3.7 (m, 4H), 3.73 (d, J=5.7 Hz, 2H), 5.06 (t, J=5.7 Hz, 1H), 6.61 (br s, 2H), 7.99 (s, 1H), 8.04 (br s, 1H), 8.65 (s, 1H), 9.79 (s, 1H)

FABMS m/z 414 (M+H)⁺ C₂₀H₂₅N₅O₅=413.

EXAMPLE 68 Compound 72

The reaction was carried out in a manner similar to that in Example 42, except that Compound 71 (34 mg, 0.082 mmol) was used in place of Compound 45. The reaction mixture was filtered, followed by addition of water and extraction with ethyl acetate. The organic layer was washed with water and a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was triturated with isopropyl ether, whereby Compound 72 (20 mg, 64%) was obtained.

¹H NMR (300 MHz, DMSO-d₆) δ 2.27 (s, 3H), 3.32 (s, 3H), 3.6-3.7 (m, 4H), 3.93 (s, 3H), 6.53 (br s, 2H), 7.60 (d, J=12.5 Hz, 1H), 7.87 (d, J=12.5 Hz, 1H), 8.02 (s, 1H), 8.03 (br s, 1H), 8.76 (s, 1H), 8.91 (s, 1H)

FABMS m/z 384 (M+H)⁺ C₁₉H₂₁N₅O₄=383.

EXAMPLE 69 Compound 73

Compound 44 (400 mg, 0.950 mmol) was dissolved in dimethylformamide (10 ml) in an atmosphere of argon, and triethylamine (5 ml), trimethylsilylacetylene (0.67 ml, 4.8 mmol), bis(triphenylphosphine)palladium chloride (67 mg, 0.095 mmol) and copper iodide (36 mg, 0.19 mmol) were added thereto, followed by stirring at 50° C. for one hour. To the reaction mixture was added water, and the resulting mixture was extracted with ethyl acetate. The organic layer was washed with water and a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/acetonitrile (3:1), whereby a trimethylsilylethynylated compound (246 mg, 59%) was obtained. The obtained compound (246 mg, 0.562 mmol) was dissolved in tetrahydrofuran (20 ml), and tetrabutylammonium trifluoride (a 1 M solution in tetrahydrofuran, 0.84 ml) was added thereto, followed by stirring at room temperature for 15 minutes. To the reaction mixture was added water, and the resulting mixture was extracted with ethyl acetate. The organic layer was washed with water and a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol (20:1), followed by trituration with isopropyl ether, whereby Compound 73 (164 mg, 80%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 2.35 (s, 3H), 3.33 (s, 6H), 3.79 (d, J=5.6 Hz, 2H), 4.69 (s, 1H), 5.05 (t, J=5.6 Hz, 1H), 8.15 (s, 1H), 8.39 (s, 1H), 8.63 (br s, 1H), 8.85 (br s, 1H), 10.1 (s, 1H)

FABMS m/z 367 (M+H)⁺ C₁₉H₁₈N₄O₄=366.

EXAMPLE 70 Compound 74

The reaction was carried out in a manner similar to that in Example 42, except that Compound 73 (30 mg, 0.082 mmol) was used in place of Compound 45. The reaction mixture was filtered, followed by addition of water. The resulting mixture was extracted three times with ethyl acetate. The organic layer was washed with water and a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by preparative thin layer chromatography with chloroform/methanol (9:1), followed by trituration with isopropyl ether, whereby Compound 74 (4.7 mg, 17%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 2.36 (s, 3H), 3.95 (s, 3H), 4.68 (s, 1H), 7.64 (d, J=12.5 Hz, 1H), 7.90 (d, J=12.5 Hz, 1H), 8.17 (s, 1H), 8.51 (s, 1H), 10.2 (br s, 1H)

FABMS m/z 335 (M+H)⁺ C₁₈H₁₄N₄O₃=334.

EXAMPLE 71 Compound 75

Compound 73 (70 mg, 0.19 mmol) was dissolved in ethyl acetate (15 ml) in an atmosphere of argon, and palladium/carbon (10%, 35 mg) was added thereto. After the argon was substituted by hydrogen, the reaction mixture was stirred at room temperature for 6 hours. Then, the hydrogen in the reactor was substituted by argon, and the reaction mixture was filtered using Celite. After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol (50:1), followed by trituration with isopropyl ether, whereby Compound 75 (12 mg, 17%) was obtained.

¹H NMR (400 MHz, CDCl₃) δ 1.49 (t, J=7.6 Hz, 3H), 2.38 (s, 3H), 3.14 (q, J=7.6 Hz, 2H), 3.47 (s, 6H), 3.73 (d, J=5.6 Hz, 2H), 5.16 (t, J=5.6 Hz, 1H), 5.62 (br s, 2H), 8.11 (s, 1H), 8.60 (s, 1H), 9.04 (br s, 1H)

FABMS m/z 371 (M+H)⁺ C₁₉H₂₂N₄O₄=370.

EXAMPLE 72 Compound 76

The reaction was carried out in a manner similar to that in Example 42, except that Compound 75 (10 mg, 0.027 mmol) was used in place of Compound 45. There action mixture was filtered, followed by addition of water and extraction with ethyl acetate. The organic layer was washed with water and a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by preparative thin layer chromatography with chloroform/methanol (9:1), followed by trituration with isopropyl ether, whereby Compound 76 (3.3 mg, 35%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 2.37 (s, 3H), 2.69 (s, 3H), 3.95 (s, 3H), 7.63 (d, J=12.5 Hz, 1H), 7.90 (d, J=12.7 Hz, 1H), 8.19 (s, 1H), 8.83 (s, 1H), 9.02 (br s, 1H), 9.17 (br s, 1H), 10.3 (br s, 1H)

FABMS m/z 353 (M+H)⁺ C₁₈H₁₆N₄O₄=352.

EXAMPLE 73 Compound 77

Compound 74 (15 mg, 0.045 mmol) was dissolved in ethyl acetate (20 ml) in an atmosphere of argon, and palladium/carbon (10%, 8 mg) was added thereto. After the argon was substituted by hydrogen, the reaction mixture was stirred at room temperature for 3 days. Then, the hydrogen in the reactor was substituted by argon, and the reaction mixture was filtered using Celite. After the solvent was evaporated under reduced pressure, the residue was purified by preparative thin layer chromatography with chloroform/methanol (9:1), whereby Compound 77 (2.0 mg, 13%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 1.39 (t, J=7.5 Hz, 3H), 2.33 (s, 3H), 3.10 (q, J=7.5 Hz, 2H), 3.94 (s, 3H), 7.64 (d, J=12.5 Hz, 1H), 7.87 (d, J=12.5 Hz, 1H), 7.88 (br s, 2H), 8.11 (s, 1H), 8.59 (s, 1H), 10.1 (s, 1H)

FABMS m/z 339 (M+H)⁺ C₁₈H₁₈N₄O₃=338.

EXAMPLE 74 Compounds 78 and 79

Compound 26 (51 mg, 0.17 mmol) was dissolved in tetrahydrofuran (7 ml), and N-bromosuccinimide (38 mg, 0.21 mmol) was added thereto under ice-cooling, followed by stirring for 10 minutes. To the reaction mixture was added water, and the resulting mixture was extracted with ethyl acetate. The organic layer was washed with water and a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by preparative thin layer chromatography with chloroform/methanol (9:1) followed by trituration with isopropyl ether, whereby Compound 78 (15 mg, 23%) and Compound 79 (22 mg, 28%) were obtained. Compound 78: ¹H NMR (400 MHz, CDCl₃) δ 3.44 (s, 6H), 3.71 (d, J=5.6 Hz, 2H), 5.15 (t, J=5.6 Hz, 1H), 5.41 (br s, 2H), 5.57 (br s, 2H), 5.87 (s, 1H), 8.54 (s, 1H)

FABMS m/z 381, 379 (M+H)⁺ C₁₅H₁₅ ⁷⁹BrN₄O₃=378.

Compound 79: ¹H NMR (400 MHz, CDCl₃) δ 3.44 (s, 6H), 3.72 (d, J=5.9 Hz, 2H), 5.15 (t, J=5.9 Hz, 1H), 5.90 (br s, 2H), 6.12 (br s, 2H), 8.56 (s, 1H)

FABMS m/z 461, 459, 457 (M+H)⁺ C₁₅H₁₄ ⁷⁹Br₂N₄O₃=456.

EXAMPLE 75 Compound 80

Compound 26 (60 mg, 0.17 mmol) was dissolved in 1,4-dioxane (8 ml), and N-bromosuccinimide (50 mg, 0.28 mmol) was added thereto under ice-cooling, followed by stirring at room temperature for 2 hours. To the reaction mixture was added water, and the resulting mixture was extracted with ethyl acetate. The organic layer was washed with water and a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by preparative thin layer chromatography with chloroform/methanol (9:1), followed by trituration with isopropyl ether, whereby Compound 80 (14 mg, 18%) was obtained.

¹H NMR (400 MHz, CDCl₃) δ 3.42 (s, 6H), 3.73 (d, J=5.6 Hz, 2H), 5.14 (t, J=5.6 Hz, 1H), 6.27 (br s, 2H), 8.22 (s, 1H), 8.61 (s, 1H)

FABMS m/z 381, 379 (M+H)⁺ C₁₅H₁₅ ⁷⁹BrN₄O₃=378.

EXAMPLE 76 Compound 81

LK6-A (62 mg, 0.20 mmol) was dissolved in chloroform/methanol (9:1, 10 ml), and N-bromosuccinimide (46 mg, 0.26 mmol) was added thereto, followed by stirring at room temperature for 15 minutes. To the reaction mixture was added water, and the resulting mixture was extracted with chloroform. The organic layer was washed with a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by preparative thin layer chromatography with chloroform/methanol (9:1), followed by trituration with isopropyl ether, whereby Compound 81 (13 mg, 13%) was obtained.

¹H NMR (400 MHz, CDCl₃) δ 2.34 (s, 3H), 3.36 (s, 3H), 3.46 (s, 3H), 4.97 (d, J=8.0 Hz, 1H), 6.82 (d, J=8.0 Hz, 1H), 8.19 (s, 1H), 8.36 (s, 1H), 10.3 (br s, 1H)

FABMS m/z 503, 501, 499 (M+H)⁺ C₁₇H₁₆ ⁷⁹Br₂N₄O₄=498.

EXAMPLE 77 Compound 82

LK6-A (93 mg, 0.30 mmol) was dissolved in chloroform/methanol (6:1, 14 ml), and N-bromosuccinimide (161 mg, 0.90 mmol) was added thereto, followed by stirring at room temperature for 1.5 hours. To the reaction mixture was added water, and the resulting mixture was extracted with chloroform. The organic layer was washed with a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol (60:1), followed by trituration with isopropyl ether, whereby Compound 82 (81 mg, 47%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 2.23 (s, 3H), 3.29 (s, 3H), 3.42 (s, 3H), 5.10 (d, J=8.1 Hz, 1H), 6.11 (d, J=8.1 Hz, 1H), 8.39 (s, 1H), 10.3 (s, 1H)

FABMS m/z 583, 581, 579, 577 (M+H)⁺ C₁₇H₁₅ ⁷⁹Br₃N₄O₄=576.

EXAMPLE 78 Compound 83

Compound 23 (20 mg, 0.050 mmol) was dissolved in dimethylformamide (2 ml), and diisopropylethylamine (0.017 ml, 0.10 mmol) and dimethylamine hydrochloride, (5.0 mg, 0.060 mmol) were added thereto, followed by stirring at room temperature for 2.5 hours. To the reaction mixture was added water, and the resulting mixture was extracted with ethyl acetate. The organic layer was washed with water and a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by preparative thin layer chromatography with chloroform/methanol (9:1), followed by trituration with isopropyl ether, whereby Compound 83 (6.2 mg, 31%) was obtained.

¹H NMR (400 MHz, CDCl₃) δ 2.34 (s, 3H), 3.07 (s, 3H), 3.20 (s, 3H), 6.93 (br d, J=12.0 Hz, 1H), 7.86 (d, J=12.7 Hz, 1H), 8.12 (s, 1H), 8.31 (br s, 2H), 8.41 (s, 1H), 10.1 (s, 1H)

FABMS m/z 404, 402 (M+H)⁺ C₁₇H₁₆ ⁷⁹BrN₅O₂=401.

EXAMPLE 79 Compound 84

The reaction was carried out in a manner similar to that in Example 42, except that Compound 78 (57 mg, 0.15 mmol) was used in place of Compound 45. The reaction mixture was filtered, followed by addition of water and extraction with ethyl acetate. The organic layer was washed with water and a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by Florisil chromatography with chloroform/methanol (9:1), followed by trituration with isopropyl ether, whereby Compound 84 (27 mg, 52%) was obtained.

¹H NMR (400 MHz, DMSO-d6) δ 3.91 (s, 3H), 5.91 (s, 1H), 7.34 (br s, 2H), 7.51 (d, J=12.5 Hz, 1H), 7.85 (d, J=12.5 Hz, 1H), 7.96 (br s, 2H), 8.32 (s, 1H)

FABMS m/z 349, 347 (M+H)⁺ C₁₄H₁₁ ⁷⁹BrN₄O₂=346.

EXAMPLE 80 Compound 85

LK6-A (310 mg, 1.00 mmol) was suspended in methanol (80 ml), and a 10 N aqueous solution of sodium hydroxide (2 ml) was added thereto, followed by heating under reflux for 4 hours. After the solvent was evaporated under reduced pressure, water was added to the residue, and the resulting mixture was extracted twice with ethyl acetate. The organic layer was washed with a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol (9:1), followed by trituration with isopropyl ether, whereby Compound 85 (81 mg, 36%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 2.80 (s, 3H), 5.94 (s, 1H), 7.06 (br s, 2H), 7.74 (br s, 2H), 8.08 (s, 1H), 8.44 (s, 1H)

FABMS m/z 227 (M+H)⁺ C₁₂H₁₀N₄O=226.

EXAMPLE 81 Compound 86

Compound 85 (45 mg, 0.20 mmol) and benzaldehyde (0.061 ml, 0.60 mmol) were dissolved in methanol (15 ml), and a 10 N aqueous solution of sodium hydroxide (0.2 ml) was added thereto, followed by stirring at room temperature for 7 days. To the reaction mixture was added water, and the resulting mixture was extracted with ethyl acetate. The organic layer was washed with a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by preparative thin layer chromatography with chloroform/methanol/aqueous ammonia (9:1:1), followed by trituration with isopropyl ether, whereby Compound 86 (29 mg, 46%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 5.96 (s, 1H), 7.35 (br s, 2H), 7.4-7.6 (m, 3H), 7.76 (br s, 2H), 7.83 (d, J=16.1 Hz, 1H), 7.9-8.1 (m, 2H), 8.11 (s, 1H), 8.63 (s, 1H), 8.82 (d, J=16.1 Hz, 1H)

FABMS m/z 315 (M+H)⁺ C₁₉H₁₄N₄O=314.

EXAMPLE 82 Compound 87

The same procedure as in Example 81 was repeated, except that 4-anisaldehyde was used in place of benzaldehyde, whereby Compound 87 (22 mg, 32%) was obtained.

¹H NMR (500 MHz, DMSO-d₆) δ 3.84 (s, 3H), 5.96 (s, 1H), 7.04 (d, J=8.8 Hz, 2H), 7.33 (br s, 2H), 7.75 (br s, 2H), 7.80 (d, J=16.0 Hz, 1H), 7.96 (d, J=8.8 Hz, 2H), 8.10 (s, 1H), 35 8.61 (s, 1H), 8.69 (d, J=16.0 Hz, 1H)

FABMS m/z 345 (M+H)⁺ C₂₀H₁₆N₄O₂=344.

EXAMPLE 83 Compound 88

The same procedure as in Example 81 was repeated, except that 4-dimethylaminobenzaldehyde was used in place of benzaldehyde, whereby Compound 88 (7.0 mg, 10%) was obtained.

¹H NMR (500 MHz, DMSO-d₆) δ 3.02 (s, 6H), 5.96 (s, 1H), 6.77 (d, J=8.9 Hz, 2H), 7.31 (br s, 2H), 7.72 (br s, 2H), 7.76 (d, J=15.8 Hz, 1H), 7.82 (d, J=8.9 Hz, 2H), 8.10 (s, 1H), 8.55 (d, J=16.0 Hz, 1H), 8.60 (s, 1H)

FABMS m/z 358 (M+H)⁺ C₂₁H₁₉N₅O=357.

EXAMPLE 84 Compound 89

The same procedure as in Example 81 was repeated, except that 4-chlorobenzaldehyde was used in place of benzaldehyde, whereby Compound 89 (18 mg, 26%) was obtained.

¹H NMR (500 MHz, DMSO-d₆) δ 5.96 (s, 1H), 7.38 (br s, 2H), 7.54 (d, J=8.5 Hz, 2H), 7.79 (br s, 2H)., 7.81 (d, J=16.2 Hz, 1H), 8.03 (d, J=8.5 Hz, 2H), 8.11 (s, 1H), 8.63 (s, 1H), 8.83 (d, J=16.1 Hz, 1H)

FABMS m/z 349 (M+H)⁺ C₁₉H₁₃ ³⁵ClN₄O=348.

EXAMPLE 85 Compound 90

The same procedure as in Example 81 was repeated, except that 4-bromobenzaldehyde was used in place of benzaldehyde, whereby Compound 90 (23 mg, 29%) was obtained.

¹H NMR (500 MHz, DMSO-d₆) δ 5.96 (s, 1H), 7.39 (br s, 2H), 7.67 (d, J=8.5 Hz, 2H), 7.80 (br s, 2H), 7.80 (d, J=16.0 Hz, 1H), 7.96 (d, J=8.6 Hz, 2H), 8.12 (s, 1H), 8.63 (s, 1H), 8.84 (d, J=16.1 Hz, 1H)

FABMS m/z 395, 393 (M+H)⁺ C₁₉H₁₃ ⁷⁹BrN₄O=392.

EXAMPLE 86 Compound 91

The same procedure as in Example 81 was repeated, except that 2-anisaldehyde was used in place of benzaldehyde, whereby Compound 91 (59 mg, 73%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 3.92 (s, 3H), 5.96 (s, 1H), 7.07 (t, J=7.4 Hz, 1H), 7.13 (d, J=8.3 Hz, 1H), 7.29 (br s, 2H), 7.46 (m, 1H), 7.75 (br s, 2H), 8.11 (s, 1H), 8.1-8.2 (m, 1H), 8.22 (d, J=16.1 Hz, 1H), 8.62 (s, 1H), 8.74 (d, J=16.4 Hz, 1H)

FABMS m/z 345 (M+H)⁺ C₂₀H₁₆N₄O₂=344.

EXAMPLE 87 Compound 92

The same procedure as in Example 81 was repeated, except that 3-anisaldehyde was used in place of benzaldehyde, whereby Compound 92 (20 mg, 29%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 3.86 (s, 3H), 5.96 (s, 1H), 7.05 (dd, J=8.1, 2.4 Hz, 1H), 7.35 (br s, 2H), 7.40 (t, J=7.8 Hz, 1H), 7.52 (t, J=2.0 Hz, 1H), 7.59 (d, J=7.6 Hz, 1H), 7.76 (br s, 2H), 7.81 (d, J=15.9 Hz, 1H), 8.11 (s, 1H), 8.63 (s, 1H), 8.78 (d, J=15.9 Hz, 1H)

FABMS m/z 345 (M+H)⁺ C₂₀H₁₆N₄O₂=344.

EXAMPLE 88 Compound 93

The same procedure as in Example 81 was repeated, except that 3,4-dimethoxybenzaldehyde was used in place of benzaldehyde, whereby Compound 93 (17 mg, 23%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 3.84 (s, 3H), 3.90 (s, 3H), 5.96 (s, 1H), 7.05 (d, J=8.3 Hz, 1H), 7.32 (br s, 2H), 7.53 (dd, J=8.3, 2.0 Hz, 1H), 7.57 (d, J=2.0 Hz, 1H), 7.75 (br s, 2H), 7.80 (d, J=15.9 Hz, 1H), 8.11 (s, 1H), 8.62 (s, 1H), 8.67 (d, J=15.9 Hz, 1H)

FABMS m/z 375 (M+H)⁺ C₂₁H₁₈N₄O₃=374.

EXAMPLE 89 Compound 94

The same procedure as in Example 81 was repeated, except that 3,4,5-trimethoxybenzaldehyde was used in place of benzaldehyde, whereby Compound 94 (42 mg, 52%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 3.74 (s, 3H), 3.91 (s, 6H), 5.96 (s, 1H), 7.29 (s, 2H), 7.31 (br s, 2H), 7.76 (br s, 2H), 7.80 (d, J=15.9 Hz, 1H), 8.11 (s, 1H), 8.63 (s, 1H), 8.70 (d, J=15.9 Hz, 1H)

FABMS m/z 405 (M+H)⁺ C₂₂H₂₀N₄O₄=404.

EXAMPLE 90 Compound 95

The same procedure as in Example 81 was repeated using Compound 85 (90 mg, 0.40 mmol) and 4-methoxymethoxybenzaldehyde (400 mg, 2.41 mmol), whereby Compound 95 (49 mg, 33%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 3.41 (s, 3H), 5.28 (s, 2H), 5.96 (s, 1H), 7.11 (d, J=8.8 Hz, 2H), 7.33 (br s, 2H), 7.75 (br s, 2H), 7.79 (d, J=16.1 Hz, 1H), 7.95 (d, J=8.8 Hz, 2H), 8.10 (s, 1H), 8.62 (s, 1H), 8.70 (d, J=16.1 Hz, 1H)

FABMS m/z 375 (M+H)⁺ C₂₁H₁₈N₄O₃=374.

EXAMPLE 91 Compound 96

Compound 95 (35 mg, 0.094 mmol) was dissolved in tetrahydrofuran (8 ml), and 1 N hydrochloric acid (2 ml) was added thereto, followed by heating under reflux for one hour. To the reaction mixture was added a saturated aqueous solution of sodium hydrogen carbonate, and the resulting mixture was extracted with ethyl acetate. The organic layer was washed with a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol/aqueous ammonia (9:1:1), whereby Compound 96 (12 mg, 39%) was obtained.

¹H NMR (400 MHz, DMSO-d₆) δ 5.96 (s, 1H), 6.87 (d, J=8.6 Hz, 2H), 7.36 (br s, 2H), 7.76 (d, J=16.1 Hz, 1H), 7.78 (br s, 2H), 7.84 (d, J=8.6 Hz, 2H), 8.12 (s, 1H), 8.61 (d, J=16.1 Hz, 1H), 8.62 (s, 1H), 10.0 (br s, 1H)

FABMS m/z 331 (M+H)⁺ C₁₉H₁₄ N₄O₂=330.

EXAMPLE 92 Compound 97

The same procedure as in Example 81 was repeated, except that 1-methyl-2-pyrrolecarboxaldehyde was used in place of benzaldehyde, whereby Compound 97 (5.6 mg, 8.8%) was obtained.

¹H NMR (300 MHz, DMSO-d ₆) δ 3.80 (s, 3H), 5.95 (s, 1H), 6.1-6.2 (m, 1H), 7.1-7.3 (m, 2H), 7.26 (br s, 2H), 7.73 (br s, 2H), 7.79 (d, J=15.6 Hz, 1H), 8.09 (s, 1H), 8.43 (d, J=15.6 Hz, 1H), 8.60 (s, 1H)

FABMS m/z 318 (M+H)⁺ C₁₈H₁₅N₅O=317.

EXAMPLE 93 Compound 98

The same procedure as in Example 81 was repeated, except that 2-thiophenecarboxaldehyde was used in place of benzaldehyde, whereby Compound 98 (12 mg, 19%) was obtained.

¹H NMR (300 MHz, DMSO-d₆) δ 5.96 (s, 1H), 7.22 (dd, J=5.0, 3.7 Hz, 1H), 7.28 (br s, 2H), 7.7-7.9 (m, 4H), 7.97 (d, J=15.8 Hz, 1H), 8.10 (s, 1H), 8.49 (d, J=15.8 Hz, 1H), 8.61 (s, 1H)

FABMS m/z 321 (M+H)⁺ C₁₇H₁₂N₄OS=320.

EXAMPLE 94 Compound 99

The same procedure as in Example 81 was repeated, except that 3-thiophenecarboxaldehyde was used in place of benzaldehyde, whereby Compound 99 (7.7 mg, 12%) was obtained.

¹H NMR (300 MHz, DMSO-d₆) δ 5.95 (s, 1H), 7.34 (br s, 2H), 7.69 (ddd, J=5.1, 2.9, 0.6 Hz, 1H), 7.78 (br s, 2H), 7.84 (d, J=16.0 Hz, 1H), 7.92 (dd, J=5.1, 0.7 Hz, 1H), 8.10 (s, 1H), 8.14 (dd, J=2.9, 0.7 Hz, 1H), 8.61 (s, 1H), 8.62 (d, J=16.0 Hz, 1H)

FABMS m/z 321 (M+H)⁺ C₁₇H₁₂N₄OS=320.

EXAMPLE 95 Compound 100

The same procedure as in Example 81 was repeated, except that 2-furancarboxaldehyde was used in place of benzaldehyde, whereby Compound 100 (24 mg, 39%) was obtained.

¹H NMR (300 MHz, DMSO-d₆) δ 5.96 (s, 1H), 6.71 (dd, J=3.3, 1.8 Hz, 1H), 7.18 (d, J=3.5 Hz, 1H), 7.21 (br s, 2H), 7.64 (d, J=16.0 Hz, 1H), 7.79 (br s, 2H), 7.92 (d, J=1.7 Hz, 1H), 8.11 (s, 1H), 8.47 (d, J=16.0 Hz, 1H), 8.60 (s, 1H)

FABMS m/z 305 (M+H)⁺ C₁₇H₁₂N₄O₂=304.

EXAMPLE 96 Compound 101

The same procedure as in Example 81 was repeated, except that 3-furancarboxaldehyde was used in place of benzaldehyde, whereby Compound 101 (2.4 mg, 3.9%) was obtained.

¹H NMR (300 MHz, DMSO-d₆) δ 5.95 (s, 1H), 7.31 (br s, 3H), 7.76 (d, J=15.8 Hz, 1H), 7.78 (br s, 2H), 7.82 (br s, 1H), 8.10 (s, 1H), 8.24 (br s, 1H), 8.53 (d, J=16.0 Hz, 1H), 8.60 (s, 1H)

FABMS m/z 305 (M+H)⁺ C₁₇H₁₂N₄O₂=304;

EXAMPLE 97 Compound 102

The same procedure as in Example 81 was repeated, except that 2-pyridinecarboxaldehyde was used in place of benzaldehyde, whereby Compound 102 (11 mg, 17%) was obtained.

¹H NMR (300 MHz, DMSO-d₆) δ 5.97 (s, 1H), 7.25 (br s, 2H), 7.44 (ddd, J=7.3, 4.8, 1.1 Hz, 1H), 7.80 (d, J=16.1 Hz, 1H), 7.82 (br s, 2H), 7.92 (td, J=7.7, 1.8 Hz, 1H), 8.12 (s, 1H), 8.16 (d, J=7.7 Hz, 1H), 8.63 (s, 1H), 8.71 (m, 1H), 8.96 (d, J=16.1 Hz, 1H)

FABMS m/z 316 (M+H)⁺ C₁₈H₁₃N₅O=315.

EXAMPLE 98 Compound 103

The same procedure as in Example 81 was repeated, except that 3-pyridinecarboxaldehyde was used in place of benzaldehyde, whereby Compound 103 (11 mg, 17%) was obtained.

¹H NMR (300 MHz, DMSO-d₆) δ 5.95 (s, 1H), 7.41 (br s, 2H), 7.52 (dd, J=7.9, 4.8 Hz, 1H), 7.81 (br s, 2H), 7.85 (d, J=16.3 Hz, 1H), 8.11 (s, 1H), 8.44 (dt, J=7.9, 1.8 Hz, 1H), 8.6-8.7 (m, 1H), 8.64 (s, 1H), 8.94 (d, J=16.1 Hz, 1H), 9.16 (d, J=1.8 Hz, 1H)

FABMS m/z 316 (M+H)⁺ C₁₈H₁₃N₅O=315.

EXAMPLE 99 Compound 104

The same procedure as in Example 81 was repeated, except that 4-pyridinecarboxaldehyde was used in place of benzaldehyde, whereby Compound 104 (8.3 mg, 20%) was obtained.

¹H NMR (300 MHz, DMSO-d₆) δ 5.96 (s, 1H), 7.41 (br s, 2H), 7.77 (d, J=16.3 Hz, 1H), 7.89 (br s, 2H), 7.94 (d, J=6.1 Hz, 2H), 8.12 (s, 1H), 8.64 (s, 1H), 8.69 (d, J=6.1 Hz, 2H), 9.01 (d, J=16.1 Hz, 1H)

FABMS m/z 316 (M+H)⁺ C₁₈H₁₃N₅O=315.

EXAMPLE 100 Compound 105

LK6-A (93 mg, 0.30 mmol) was dissolved in dimethyl sulfoxide (10 ml), and piperazine (54 mg, 0.60 mmol) was added thereto, followed by stirring at room temperature for 2 hours. To the reaction mixture was added chloroform (100 ml), and the resulting mixture was passed through a silica gel column for adsorption, followed by elution with chloroform/methanol/aqueous ammonia (9:1:1). The eluate was triturated with isopropyl ether, whereby Compound 105 (95 mg, 87%) was obtained.

¹H NMR (300 MHz, DMSO-d₆) δ 2.35 (s, 3H), 2.79 (m, 4H), 3.48 (m, 4H), 7.06 (d, J=13.0 Hz, 1H), 7.79 (d, J=12.8 Hz, 1H), 8.00 (br s, 2H), 8.13 (s, 1H), 8.31 (s, 1H), 8.33 (s, 1H), 8.61 (s, 1H), 10.1 (br s, 1H)

FABMS m/z 365 (M+H)⁺ C₁₉H₂₀N₆O₂=364.

EXAMPLE 101 Compound 106

LK6-A (31 mg, 0.10 mmol) was dissolved in dimethyl sulfoxide (3 ml), and 1-acetylpiperazine (64 mg, 0.50 mmol) was added thereto, followed by stirring at room temperature for 5 hours. To the reaction mixture was added water, and the resulting mixture was extracted with chloroform. The organic layer was washed with a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by preparative thin layer chromatography with chloroform/methanol (9:1), whereby Compound 106 (8.3 mg, 20%) was obtained.

¹H NMR (300 MHz, DMSO-d₆) δ 2.07 (s, 3H), 2.36 (s, 3H), 3.59 (m, 8H) 7.13 (d, J 13.0 Hz, 1H), 7.85 (d, J=13.0 Hz, 1H), 8.01 (br s, 2H), 8.13 (s, 1H), 8.34 (s, 1H), 8.61 (s, 1H), 10.1 (br s, 1H)

FABMS m/z 407 (M+H)⁺ C₂H₂₂N₆O₃=406.

EXAMPLE 102 Compound 107

Compound 105 (7.2 mg, 0.020 mmol) was dissolved in dimethylformamide (1 ml), and triethylamine (0.0028 ml, 0.020 mmol) and benzoyl chloride (0.0028 ml, 0.024 mmol) were added thereto, followed by stirring at room temperature for 15 minutes. To the reaction mixture was added water, and the resulting mixture was extracted with ethyl acetate. The organic layer was washed with water and a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by preparative thin layer chromatography with chloroform/methanol (9:1), whereby Compound 107 (2.2 mg, 24%) was obtained.

¹H NMR (300 MHz, CDCl 3) δ 2.39 (s, 3H), 3.54 (m, 4H), 3.75 (m, 4H), 6.72 (d, J=12.8 Hz, 1H), 7.26 (m, 2H), 7.60 (m, 1H), 7.95 (d, J=12.8 Hz, 1H), 8.12 (d, J=7.2 Hz, 2H), 8.12 (s, 1H), 8.41 (s, 1H), 8.80 (s, 1H), 9.24 (br s, 1H)

FABMS m/z 469 (M+H)⁺ C₂₆H₂₄N₆O₃=468;

EXAMPLE 103 Compound 108

Compound 105 (6.6 mg, 0.018 mmol) was dissolved in tetrahydrofuran (3 ml), and N-hydroxysuccinidyl 4-azidosalicylate (0.0050 mg, 0.018 mmol) and 4-dimethylaminopyridine (0.0020 ml, 0.016 mmol) were added thereto, followed by stirring at room temperature for 24 minutes. To the reaction mixture was added water, and the resulting mixture was extracted with ethyl acetate. The organic layer was washed with water and a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by preparative thin layer chromatography with chloroform/methanol (9:1), whereby Compound 108 (4.1 mg, 43%) was obtained.

¹H NMR (300 MHz, DMSO-d₆) δ 2.34 (s, 3H), 3.3-3.9 (m, 8H), 6.61 (d, J=2.0 Hz, 1H), 6.65 (dd, J=8.1, 2.2 Hz, 1H), 7.14 (br d, J=13.0 Hz, 1H), 7.24 (d, J=8.1 Hz, 1H), 7.84 (br d, J=13.2 Hz, 1H), 8.06 (br s, 2H), 8.13 (s, 1H)., 8.34 (s, 1H), 8.61 (s, 1H), 10.1 (br s, 1H), 10.3 (s, 1H)

FABMS m/z 526 (M+H)⁺ C₂₆H₂₃N₆O₄=525.

EXAMPLE 104 Compound 109

Compound 105 (7.3 mg, 0.020 mmol) was dissolved in dimethylformamide (1 ml), and N-hydroxysuccinidyl 4-azidobenzoate (0.0052 mg, 0.020 mmol) was added thereto, followed by stirring at room temperature for 118 minutes. To the reaction mixture was added water, and the resulting mixture was extracted with ethyl acetate. The organic layer was washed with water and a saturated aqueous solution of sodium chloride, and then dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by preparative thin layer chromatography with chloroform/methanol (9:1), whereby Compound 109 (5.2 mg, 51%) was obtained.

¹H NMR (300 MHz, CDCl₃) δ 2.38 (s, 3H), 3.53 (m, 4H), 3.76 (m, 4H), 5.83 (br s, 2H), 6.74 (d, J=13.0 Hz, 1H), 7.10 (d, J=8.6 Hz, 2H), 7.47 (d, J=8.6 Hz, 2H), 7.92 (d, J=12.8 Hz, 1H), 8.12 (s, 1H), 8.39 (s, 1H), 8.75 (s, 1H), 9.17 (br s, 1H)

FABMS m/z 510 (M+H)⁺ C₂₆H₂₃N₉O₃=509.

EXAMPLE 105 Compound 110

To LK6-A (40.9 mg, 0.13 mmol) was added acetic anhydride (4 ml), followed by stirring at room temperature for 3 hours. To the reaction mixture was added a saturated aqueous solution of sodium hydrogen carbonate, and the resulting mixture was extracted with chloroform. The organic layer was dried over anhydrous sodium sulfate. After the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol (49:1), whereby Compound 110 (30.7 mg, 51%) was obtained.

¹H NMR (500 MHz, DMSO-d₆) δ 2.10 (s, 3H), 2.16 (s, 3H), 2.30 (s, 3H), 2.41 (s, 3H), 3.96 (s, 3H), 7.53 (d, J=12.5 Hz, 1H), 7.95 (d, J=12.5 Hz, 1H), 8.01 (s, 1H), 8.13 (s, 1H), 9.21 (s, 1H), 10.13 (s, 1H), 10.74 (s, 1H)

FABMS m/z 455 (M+H)⁺ C₂₂H₂₂N₄O₇=454.

EXAMPLE 106 Compound 111

Compound 25 (342 mg, 1.00 mmol) was dissolved in acetic anhydride (20 ml), and the resulting solution was stirred at room temperature for 3 hours. After the acetic anhydride was evaporated under reduced pressure, the residue was purified by silica gel column chromatography with chloroform/methanol (50:1), followed by trituration with isopropyl ether, whereby Compound 111 (166 mg, 34%) was obtained.

¹H NMR (400 MHz, CDCl₃) δ 2.17 (s, 3H), 2.23 (s, 3H), 2.36 (s, 3H), 2.45 (s, 3H), 3.45 (s, 6H), 3.64 (dd, J=16.0, 5.6 Hz, 1H), 3.69 (dd, J=16.0, 5.6 Hz, 1H), 5.11 (t, J=5.6 Hz, 1H), 7.78 (d, J=1.0 Hz, 1H), 8.17 (d, J=1.0 Hz, 1H), 8.79 (br s, 1H), 9.70 (br s, 1H), 10.9 (br s, 1H)

FABMS m/z 487 (M+H)⁺ C₂₃H₂₆N₄O₇=486.

EXAMPLE 107 Compounds 112 and 113

Compound 111 (70 mg, 0.14 mmol) was dissolved in ethyl acetate/methanol (3:1, 20 ml) in an atmosphere of argon, and palladium/carbon (10%, 30 mg) was added thereto. After the argon was substituted by hydrogen, the reaction mixture was stirred at room temperature for 2.5 hours. Then, the hydrogen in the reactor was substituted by argon, and the reaction mixture was filtered using Celite. After the solvent was evaporated under reduced pressure, the residue was purified by preparative thin layer chromatography with chloroform/methanol (9:1), followed by trituration with isopropyl ether, whereby Compound 112 (19 mg, 32%) and Compound 113 (23 mg, 32%) were obtained.

Compound 112: ¹H NMR (400 MHz, CDCl₃) δ 2.22 (s, 3H), 2.36 (s, 3H), 2.45 (s, 3H), 3.45 (s, 6H), 3.67 (d, J=5.6 Hz, 2H), 5.09 (t, J=5.6 Hz, 1H), 5.36 (d, J=1.2 Hz, 2H), 7.93 (t, J=1.2 Hz, 1H), 9.62 (s, 1H)

FABMS m/z 429 (M+H)⁺ C₂₁H₂₄N₄O₅=428.

Compound 113: ¹H NMR (400 MHz, CDCl₃) δ 2.0-2.1 (m, 1H), 2.1-2.2 (m, 1H), 2.19 (s, 3H), 2.31 (s, 3H), 2.41 (s, 3H), 3.42 (s, 3H), 3.44 (s, 3H), 4.27 (br s, 1H), 4.70 (t, J=5.4 Hz, 1H), 5.03 (dd, J=9.5, 2.9 Hz, 1H), 5.25 (s, 2H), 7.28 (s, 1H), 8.60 (s, 1H), 9.51 (br s, 1H), 11.3 (br s, 1H)

FABMS m/z 431 (M+H)⁺ C₂₁H₂₆N₄O₅=430.

EXAMPLE 108 Compound 114

Compound 110 (60 mg, 0.13 mmol) was dissolved in ethyl acetate/methanol (9:1, 20 ml) in an atmosphere of argon, and palladium/carbon (10%, 30 mg) was added thereto. After the argon was substituted by hydrogen, the reaction mixture was stirred at room temperature for 12 hours. Then, the hydrogen in the reactor was substituted by argon, and the reaction mixture was filtered using Celite. After the solvent was evaporated under reduced pressure, the residue was purified by preparative thin layer chromatography with chloroform/methanol (9:1), followed by trituration with isopropyl ether, whereby Compound 114 (22 mg, 43%) was obtained.

¹H NMR (400 MHz, CDCl₃+CD₃OD) δ 2.21 (s, 3H), 2.35 (s, 3H), 2.44 (s, 3H), 3.42 (s, 3H), 3.58 (t, J=6.2 Hz, 2H), 3.89 (t, J=6.2 Hz, 2H), 5.32 (d, J=1.5 Hz, 2H), 7.88 (s, 1H), 9.60 (s, 1H)

FABMS m/z 399 (M+H)⁺ C₂₀H₂₂N₄O₅=398. 

What is claimed is:
 1. A compound represented by formula (I):

wherein R¹ represents lower alkyl (optionally substituted by one or more substituents independently selected from the group consisting of lower alkyl, hydroxy, lower alkoxy and halogen), lower alkanoyl (the lower alkyl moiety being optionally substituted by one or more substituents independently selected from the group consisting of lower alkyl, hydroxy, lower alkoxy and halogen), carboxy, lower alkoxycarbonyl,

(wherein n represents 1 or 2) or COCH═CHR⁹ {wherein R⁹ represents substituted or unsubstituted lower alkoxy, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl or NR¹⁰R¹¹ (wherein R¹⁰ and R¹¹ independently represent hydrogen, substituted or unsubstituted lower alkyl, substituted or unsubstituted lower alkenyl, substituted or unsubstituted lower alkynyl, substituted or unsubstituted aralkyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted heteroaryl-substituted lower alkyl, substituted or unsubstituted tetrahydropyranyl, or substituted or unsubstituted tetrahydropyranylmethyl, or R¹⁰ and R¹¹ are combined together with the adjoining N to form a substituted or unsubstituted heterocyclic group)}; R² represents NR¹³R¹⁴ (wherein R¹³ and R¹⁴ have the same significances as R¹⁰ and R¹¹, respectively); R⁴ and R⁵ independently represent hydrogen, substituted or unsubstituted lower alkyl, substituted or unsubstituted lower alkanoyl, substituted or unsubstituted lower alkoxycarbonyl, substituted or unsubstituted aralkyloxycarbonyl, or substituted or unsubstituted heteroaryl-substituted lower alkoxycarbonyl; R⁶ represents hydrogen or halogen; and R⁷ and R⁸ independently represent hydrogen, substituted or unsubstituted lower alkyl, or substituted or unsubstituted lower alkanoyl; or a pharmaceutically acceptable salt thereof.
 2. The compound or the pharmaceutically acceptable salt thereof according to claim 1, wherein R¹ represents COCH═CHR⁹; R⁴, R⁵ and R⁶ represent hydrogen; and R⁷ and R⁸ independently represent hydrogen or acetyl.
 3. The compound or the pharmaceutically acceptable salt thereof according to claim 1, wherein R¹ represents said optionally substituted lower alkyl or said optionally substituted lower alkanoyl; R⁴, R⁵ and R⁶ represent hydrogen; and R⁷ and R⁸ independently represent hydrogen or acetyl.
 4. The compound or the pharmaceutically acceptable salt thereof according to claim 1, wherein R¹ represents:

wherein R⁴, R⁵ and R⁶ represent hydrogen; and R⁷ and R⁸ independently represent hydrogen or acetyl.
 5. The compound or the pharmaceutically acceptable salt thereof according to claim 1, wherein R¹ represents (E)-3-methoxyacryloyl; R⁴ represents hydrogen; and R⁵ represents substituted or unsubstituted lower alkoxycarbonyl or substituted or unsubstituted aralkyloxycarbonyl.
 6. The compound or the pharmaceutically acceptable salt thereof according to claim 1, wherein R¹ represents COCHR¹⁵CH (OCH₃)₂ (wherein R¹⁵ represents hydrogen or lower alkyl); R⁴ and R⁵ independently represent hydrogen or lower alkyl; and R⁷ and R⁸ independently represent hydrogen, substituted or unsubstituted lower alkyl or acetyl.
 7. The compound or the pharmaceutically acceptable salt thereof according to claim 1, wherein R¹ represents COCHR^(15a)CH (OCH₃)₂ (wherein R^(15a) represents hydrogen or halogen); R⁴ and R⁵ represent hydrogen; and R⁷ and R⁸ independently represent hydrogen or acetyl.
 8. The compound or the pharmaceutically acceptable salt thereof according to claim 1, wherein R¹ represents 1-hydroxy-3-methoxypropyl; R⁴ and R⁵ represent hydrogen; and R⁷ and R⁸ independently represent hydrogen or acetyl.
 9. The compound or the pharmaceutically acceptable salt thereof according to claim 1, wherein R⁴ represents hydrogen; R⁵ represents substituted or unsubstituted lower alkanoyl; R⁷ represents hydrogen; and R⁸ represents acetyl.
 10. A pharmaceutical composition comprising at least one of the compounds or the pharmaceutically acceptable salts thereof according to any of claims 1-9 and a pharmaceutically acceptable carrier.
 11. A method for immunosuppression which comprises the steps of: selecting at least one of the compounds or the pharmaceutically acceptable salts thereof according to any of claims 1-9, and administering said compound or salt to a patient in need thereof.
 12. The compound or the pharmaceutically acceptable salt thereof according to claim 1, wherein R¹ represents (E)-3-methoxyacryloyl.
 13. The compound or the pharmaceutically acceptable salt thereof according to claim 12, wherein R⁴ and R⁵ represent hydrogen; and R⁷ and R⁸ independently represent hydrogen or acetyl.
 14. The compound or the pharmaceutically acceptable salt thereof according to claim 12 or 13, wherein R¹³ represents hydrogen; and R¹⁴ represents substituted or unsubstituted lower alkyl, substituted or unsubstituted lower alkynyl or substituted or unsubstituted aryl.
 15. A pharmaceutical composition comprising at least one of the compounds or the pharmaceutically acceptable salts thereof according to claim 12 or 13 and a pharmaceutically acceptable carrier.
 16. A pharmaceutical composition comprising at least one of the compounds or the pharmaceutically acceptable salts thereof according to claim 14 and a pharmaceutically acceptable carrier.
 17. A method for immunosuppression which comprises the steps of: selecting at least one of the compounds or the pharmaceutically acceptable salts thereof according to any of claim 12 or 13, and administering said compound or salt to a patient in need thereof.
 18. A method for immunosuppression which comprises the steps of: selecting at least one of the compounds or the pharmaceutically acceptable salts thereof according to claim 14, and administering said compound or salt to a patient in need thereof. 